Warning
This project is being split into 3 separate projects:
friendly_traceback,friendly, andfriendly_idle.
The documentation does not reflect this change.
If you are a end-user, just install friendly until further notice.
Friendly tracebacks - in English¶
Friendly aims to provide friendlier feedback when an exception is raised than what is done by Python. Below, we can find some examples. SyntaxError cases, as well as TabError and IndentationError cases, are shown in a separate page. Not all cases handled by friendly are included here.
Note
The content of this page is generated by running
trb_english.py located in the tests/ directory.
This needs to be done explicitly, independently of updating the
documentation using Sphinx.
Friendly version: 0.3.142 Python version: 3.8.10
ArithmeticError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_arithmetic_error.py", line 9, in test_Generic
raise ArithmeticError('error')
ArithmeticError: error
`ArithmeticError` is the base class for those built-in exceptions
that are raised for various arithmetic errors.
It is unusual that you are seeing this exception;
normally, a more specific exception should have been raised.
Exception raised on line 9 of file TESTS:\runtime\test_arithmetic_error.py.
7: # Usually, a subclass such as ZeroDivisionError, etc., would
8: # likely be raised.
--> 9: raise ArithmeticError('error')
10: except ArithmeticError as e:
ArithmeticError: <class ArithmeticError>
AssertionError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_assertion_error.py", line 8, in test_Generic
raise AssertionError("Fake message")
AssertionError: Fake message
In Python, the keyword `assert` is used in statements of the form
`assert condition`, to confirm that `condition` is not `False`,
nor equivalent to `False` such as an empty list, etc.
If `condition` is `False` or equivalent, an `AssertionError` is raised.
Exception raised on line 8 of file TESTS:\runtime\test_assertion_error.py.
6: # We raise it explicitly, rather than with the keyword assert, since
7: # we don't want pytest to rewrite out test.
--> 8: raise AssertionError("Fake message")
9: except AssertionError as e:
AssertionError: <class AssertionError>
AttributeError¶
Attribute from other module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 299, in test_Attribute_from_other_module
keyword.pi
AttributeError: module 'keyword' has no attribute 'pi'
Did you mean one of the following modules: `math, cmath`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
Instead of the module `keyword`, perhaps you wanted to use
the attribute `pi` of one of the following modules:
`math, cmath`.
Exception raised on line 299 of file TESTS:\runtime\test_attribute_error.py.
297: import cmath
298: try:
-->299: keyword.pi
300: except AttributeError as e:
keyword: <module keyword> from PYTHON_LIB:\keyword.py
Builtin function¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 217, in test_Builtin_function
len.text
AttributeError: 'builtin_function_or_method' object has no attribute 'text'
Did you mean `len(text)`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
`len` is a function. Perhaps you meant to write
`len(text)`
Exception raised on line 217 of file TESTS:\runtime\test_attribute_error.py.
215: text = 'Hello world!'
216: try:
-->217: len.text
218: except AttributeError as e:
text: 'Hello world!'
len: <builtin function len>
Builtin module with no file¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 234, in test_Builtin_module_with_no_file
sys.foo
AttributeError: module 'sys' has no attribute 'foo'
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
Python tells us that no object with name `foo` is
found in module `sys`.
Exception raised on line 234 of file TESTS:\runtime\test_attribute_error.py.
232:
233: try:
-->234: sys.foo
235: except AttributeError as e:
sys: <module sys (builtin)>
Circular import¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 329, in test_Circular_import
import my_turtle1
File "TESTS:\my_turtle1.py", line 4, in <module>
a = my_turtle1.something
AttributeError: partially initialized module 'my_turtle1' has no attribute 'something' (most likely due to a circular import)
Did you give your program the same name as a Python module?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
I suspect that you used the name `my_turtle1.py` for your program
and that you also wanted to import a module with the same name
from Python's standard library.
If so, you should use a different name for your program.
Execution stopped on line 329 of file TESTS:\runtime\test_attribute_error.py.
327: stdlib_modules.names.append("my_turtle1")
328: try:
-->329: import my_turtle1
330: except AttributeError as e:
Exception raised on line 4 of file TESTS:\my_turtle1.py.
2: import my_turtle1
3:
-->4: a = my_turtle1.something
^^^^^^^^^^^^^^^^^^^^
my_turtle1: <module my_turtle1> from TESTS:\my_turtle1.py
Circular import b¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 346, in test_Circular_import_b
import circular_c
File "TESTS:\circular_c.py", line 4, in <module>
a = circular_c.something
AttributeError: partially initialized module 'circular_c' has no attribute 'something' (most likely due to a circular import)
You have a circular import.
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
Python indicated that the module `{module}` was not fully imported.
This can occur if, during the execution of the code in module `circular_c`
an attempt is made to import the same module again.
Execution stopped on line 346 of file TESTS:\runtime\test_attribute_error.py.
344: def test_Circular_import_b():
345: try:
-->346: import circular_c
347: except AttributeError as e:
Exception raised on line 4 of file TESTS:\circular_c.py.
2: import circular_c
3:
-->4: a = circular_c.something
^^^^^^^^^^^^^^^^^^^^
circular_c: <module circular_c> from TESTS:\circular_c.py
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 24, in test_Generic
A.x # testing type
AttributeError: type object 'A' has no attribute 'x'
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `A` has no attribute named `x`.
Exception raised on line 24 of file TESTS:\runtime\test_attribute_error.py.
22:
23: try:
-->24: A.x # testing type
25: except AttributeError as e:
A: <class A> from test_attribute_error.test_Generic
Generic different frame¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 47, in test_Generic_different_frame
a.attr
AttributeError: 'A' object has no attribute 'attr'
Did you mean `attr2`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `a` has no attribute named `attr`.
Perhaps you meant to write `a.attr2` instead of `a.attr`
Exception raised on line 47 of file TESTS:\runtime\test_attribute_error.py.
45: a = f()
46: try:
-->47: a.attr
48: except AttributeError as e:
a: <f.A object> from test_attribute_error.test_Generic_different_frame
Generic instance¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 65, in test_Generic_instance
a.x
AttributeError: 'A' object has no attribute 'x'
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `a` has no attribute named `x`.
Exception raised on line 65 of file TESTS:\runtime\test_attribute_error.py.
63: a = A()
64: try:
-->65: a.x
66: except AttributeError as e:
a: <A object> from test_attribute_error.test_Generic_instance
Module attribute typo¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 142, in test_Module_attribute_typo
math.cost
AttributeError: module 'math' has no attribute 'cost'
Did you mean `cos`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
Instead of writing `math.cost`, perhaps you meant to write one of
the following names which are attributes of module `math`:
`cos, cosh, acos`
Exception raised on line 142 of file TESTS:\runtime\test_attribute_error.py.
140:
141: try:
-->142: math.cost
143: except AttributeError as e:
math: <module math (builtin)>
Nonetype¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 181, in test_Nonetype
a.b
AttributeError: 'NoneType' object has no attribute 'b'
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
You are attempting to access the attribute `b`
for a variable whose value is `None`.
Exception raised on line 181 of file TESTS:\runtime\test_attribute_error.py.
179: a = None
180: try:
-->181: a.b
182: except AttributeError as e:
a: None
Object attribute typo¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 81, in test_Object_attribute_typo
a.appendh(4)
AttributeError: 'list' object has no attribute 'appendh'
Did you mean `append`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `a` has no attribute named `appendh`.
Perhaps you meant to write `a.append` instead of `a.appendh`
Exception raised on line 81 of file TESTS:\runtime\test_attribute_error.py.
79: try:
80: a = [1, 2, 3]
-->81: a.appendh(4)
^^^^^^^^^
82: except AttributeError as e:
a: [1, 2, 3]
Perhaps comma¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 200, in test_Perhaps_comma
a = [abcd
AttributeError: 'str' object has no attribute 'defg'
Did you mean to separate object names by a comma?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
`defg` is not an attribute of `abcd`.
However, both `abcd` and `defg` are known objects.
Perhaps you wrote a period to separate these two objects,
instead of using a comma.
Exception raised on line 200 of file TESTS:\runtime\test_attribute_error.py.
198: # fmt: off
199: try:
-->200: a = [abcd
201: .defg]
abcd: 'hello'
defg: 'world'
Shadow stdlib module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 163, in test_Shadow_stdlib_module
turtle.Pen
AttributeError: module 'turtle' has no attribute 'Pen'
Did you give your program the same name as a Python module?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
You imported a module named `turtle` from `TESTS:\turtle.py`.
There is also a module named `turtle` in Python's standard library.
Perhaps you need to rename your module.
Exception raised on line 163 of file TESTS:\runtime\test_attribute_error.py.
161:
162: try:
-->163: turtle.Pen
164: except AttributeError as e:
turtle: <module turtle> from TESTS:\turtle.py
Tuple by accident¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 269, in test_Tuple_by_accident
something.upper()
AttributeError: 'tuple' object has no attribute 'upper'
Did you write a comma by mistake?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
`something` is a tuple that contains a single item
which does have `'upper'` as an attribute.
Perhaps you added a trailing comma by mistake at the end of the line
where you defined `something`.
Exception raised on line 269 of file TESTS:\runtime\test_attribute_error.py.
267: something = "abc", # note trailing comma
268: try:
-->269: something.upper()
^^^^^^^^^^^^^^^
270: except AttributeError as e:
something: ('abc',)
Use builtin¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 97, in test_Use_builtin
a.length()
AttributeError: 'list' object has no attribute 'length'
Did you mean `len(a)`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `a` has no attribute named `length`.
Perhaps you can use the Python builtin function `len` instead:
`len(a)`.
Exception raised on line 97 of file TESTS:\runtime\test_attribute_error.py.
95: try:
96: a = [1, 2, 3]
-->97: a.length()
^^^^^^^^
98: except AttributeError as e:
a: [1, 2, 3]
Use join with str¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 313, in test_Use_join_with_str
a = ['a', '2'].join('abc') + ['b', '3'].join('\n')
AttributeError: 'list' object has no attribute 'join'
Did you mean `'abc'.join(['a', '2'])`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `['a', '2']` has no attribute named `join`.
Perhaps you wanted something like `'abc'.join(['a', '2'])`.
Exception raised on line 313 of file TESTS:\runtime\test_attribute_error.py.
311: def test_Use_join_with_str():
312: try:
-->313: a = ['a', '2'].join('abc') + ['b', '3'].join('\n')
^^^^^^^^^^^^^^^
314: except AttributeError as e:
Use synonym¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 113, in test_Use_synonym
a.add(4)
AttributeError: 'list' object has no attribute 'add'
Did you mean `append`?
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `a` has no attribute named `add`.
However, `a` has the following attributes with similar meanings:
`append, extend, insert`.
Exception raised on line 113 of file TESTS:\runtime\test_attribute_error.py.
111: try:
112: a = [1, 2, 3]
-->113: a.add(4)
^^^^^
114: except AttributeError as e:
a: [1, 2, 3]
Using slots¶
Traceback (most recent call last):
File "TESTS:\runtime\test_attribute_error.py", line 254, in test_Using_slots
f.b = 1
AttributeError: 'F' object has no attribute 'b'
An `AttributeError` occurs when the code contains something like
`object.x`
and `x` is not a method or attribute (variable) belonging to `object`.
The object `f` has no attribute named `b`.
Note that object `f` uses `__slots__` which prevents
the creation of new attributes.
The following are some of its known attributes:
`a`.
Exception raised on line 254 of file TESTS:\runtime\test_attribute_error.py.
252: f = F()
253: try:
-->254: f.b = 1
255: except AttributeError as e:
f: <F object> from test_attribute_error.test_Using_slots
FileNotFoundError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_file_not_found_error.py", line 6, in test_Generic
open("does_not_exist")
FileNotFoundError: [Errno 2] No such file or directory: 'does_not_exist'
A `FileNotFoundError` exception indicates that you
are trying to open a file that cannot be found by Python.
This could be because you misspelled the name of the file.
In your program, the name of the
file that cannot be found is `does_not_exist`.
Exception raised on line 6 of file TESTS:\runtime\test_file_not_found_error.py.
4: def test_Generic():
5: try:
-->6: open("does_not_exist")
7: except FileNotFoundError as e:
open: <builtin function open>
ImportError¶
Circular import¶
Traceback (most recent call last):
File "TESTS:\runtime\test_import_error.py", line 58, in test_Circular_import
import circular_a
File "TESTS:\circular_a.py", line 2, in <module>
import circular_b
File "TESTS:\circular_b.py", line 2, in <module>
from circular_a import a
ImportError: cannot import name 'a' from partially initialized module 'circular_a' (most likely due to a circular import) (C:\Users\andre\github\friendly-traceback\tests\circular_a.py)
An `ImportError` exception indicates that a certain object could not
be imported from a module or package. Most often, this is
because the name of the object is not spelled correctly.
The object that could not be imported is `a`.
The module or package where it was
expected to be found is `circular_a`.
The problem was likely caused by what is known as a 'circular import'.
First, Python imported and started executing the code in file
'TESTS:\runtime\test_import_error.py'.
which imports module `circular_a`.
During this process, the code in another file,
'TESTS:\circular_b.py'
was executed. However in this last file, an attempt was made
to import the original module `circular_a`
a second time, before Python had completed the first import.
Execution stopped on line 58 of file TESTS:\runtime\test_import_error.py.
56: def test_Circular_import():
57: try:
-->58: import circular_a
59: except ImportError as e:
Exception raised on line 2 of file TESTS:\circular_b.py.
1: """File used in for test_circular_import() in test_import_error.py"""
-->2: from circular_a import a
Simple import error¶
Traceback (most recent call last):
File "TESTS:\runtime\test_import_error.py", line 44, in test_Simple_import_error
from math import Pi
ImportError: cannot import name 'Pi' from 'math' (unknown location)
Did you mean `pi`?
An `ImportError` exception indicates that a certain object could not
be imported from a module or package. Most often, this is
because the name of the object is not spelled correctly.
Perhaps you meant to import `pi` (from `math`) instead of `Pi`
Exception raised on line 44 of file TESTS:\runtime\test_import_error.py.
42:
43: try:
-->44: from math import Pi
45: except ImportError as e:
IndexError¶
Empty¶
Traceback (most recent call last):
File "TESTS:\runtime\test_index_error.py", line 38, in test_Empty
c = a[1]
IndexError: list index out of range
`a` contains no item.
An `IndexError` occurs when you try to get an item from a list,
a tuple, or a similar object (sequence), and use an index which
does not exist; typically, this happens because the index you give
is greater than the length of the sequence.
You have tried to get the item with index `1` of `a`,
a `list` which contains no item.
Exception raised on line 38 of file TESTS:\runtime\test_index_error.py.
36: a = []
37: try:
-->38: c = a[1]
^^^^
39: except IndexError as e:
a: []
Long list¶
Traceback (most recent call last):
File "TESTS:\runtime\test_index_error.py", line 24, in test_Long_list
print(a[60], b[0])
IndexError: list index out of range
An `IndexError` occurs when you try to get an item from a list,
a tuple, or a similar object (sequence), and use an index which
does not exist; typically, this happens because the index you give
is greater than the length of the sequence.
You have tried to get the item with index `60` of `a`,
a `list` of length `40`.
The valid index values of `a` are integers ranging from
`-40` to `39`.
Exception raised on line 24 of file TESTS:\runtime\test_index_error.py.
22: b = tuple(range(50))
23: try:
-->24: print(a[60], b[0])
^^^^^
25: except IndexError as e:
a: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, ...]
len(a): 40
Short tuple¶
Traceback (most recent call last):
File "TESTS:\runtime\test_index_error.py", line 8, in test_Short_tuple
print(a[3], b[2])
IndexError: tuple index out of range
Remember: the first item of a `tuple` is not at index 1 but at index 0.
An `IndexError` occurs when you try to get an item from a list,
a tuple, or a similar object (sequence), and use an index which
does not exist; typically, this happens because the index you give
is greater than the length of the sequence.
You have tried to get the item with index `3` of `a`,
a `tuple` of length `3`.
The valid index values of `a` are integers ranging from
`-3` to `2`.
Exception raised on line 8 of file TESTS:\runtime\test_index_error.py.
6: b = [1, 2, 3]
7: try:
--> 8: print(a[3], b[2])
^^^^
9: except IndexError as e:
a: (1, 2, 3)
KeyError¶
ChainMap¶
Traceback (most recent call last):
File "PYTHON_LIB:\collections\__init__.py", line 965, in pop
return self.maps[0].pop(key, *args)
KeyError: 42
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 62, in test_ChainMap
d.pop(42)
File "PYTHON_LIB:\collections\__init__.py", line 967, in pop
raise KeyError('Key not found in the first mapping: {!r}'.format(key))
KeyError: 'Key not found in the first mapping: 42'
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
The key `42` cannot be found in `d`, an object of type `ChainMap`.
Execution stopped on line 62 of file TESTS:\runtime\test_key_error.py.
60: d = ChainMap({}, {})
61: try:
-->62: d.pop(42)
63: except KeyError as e:
d: ChainMap({}, {})
d.pop: <bound method ChainMap.pop of ChainMap({}, {})>
Exception raised on line 967 of file PYTHON_LIB:\collections\__init__.py.
965: return self.maps[0].pop(key, *args)
966: except KeyError:
-->967: raise KeyError('Key not found in the first mapping: {!r}'.format(key))
key: 42
KeyError: <class KeyError>
format: <builtin function format>
'Key not found in the first mapping: {!r}'.format: <builtin method format of str object>
Forgot to convert to string¶
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 115, in test_Forgot_to_convert_to_string
print(squares[2])
KeyError: 2
Did you forget to convert `2` into a string?
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
The key `2` cannot be found in the dict `squares`.
`squares` contains a string key which is identical to `str(2)`.
Perhaps you forgot to convert the key into a string.
Exception raised on line 115 of file TESTS:\runtime\test_key_error.py.
113: squares = {"1": 1, "2": 4, "3": 9}
114: try:
-->115: print(squares[2])
^^^^^^^^^^
116: except KeyError as e:
squares: {'1': 1, '2': 4, '3': 9}
Generic key error¶
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 44, in test_Generic_key_error
d["c"]
KeyError: 'c'
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
The key `'c'` cannot be found in the dict `d`.
Exception raised on line 44 of file TESTS:\runtime\test_key_error.py.
42: d = {"a": 1, "b": 2}
43: try:
-->44: d["c"]
45: except KeyError as e:
d: {'a': 1, 'b': 2}
Popitem empty ChainMap¶
Traceback (most recent call last):
File "PYTHON_LIB:\collections\__init__.py", line 958, in popitem
return self.maps[0].popitem()
KeyError: 'popitem(): dictionary is empty'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 26, in test_Popitem_empty_ChainMap
alpha.popitem()
File "PYTHON_LIB:\collections\__init__.py", line 960, in popitem
raise KeyError('No keys found in the first mapping.')
KeyError: 'No keys found in the first mapping.'
`alpha` is an empty `ChainMap`.
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
You tried to retrieve an item from `alpha` which is an empty `ChainMap`.
Execution stopped on line 26 of file TESTS:\runtime\test_key_error.py.
24: alpha = ChainMap({}, {})
25: try:
-->26: alpha.popitem()
27: except KeyError as e:
alpha: ChainMap({}, {})
alpha.popitem: <bound method ChainMap.popitem of ChainMap({}, {})>
Exception raised on line 960 of file PYTHON_LIB:\collections\__init__.py.
958: return self.maps[0].popitem()
959: except KeyError:
-->960: raise KeyError('No keys found in the first mapping.')
KeyError: <class KeyError>
Popitem empty dict¶
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 8, in test_Popitem_empty_dict
d.popitem()
KeyError: 'popitem(): dictionary is empty'
`d` is an empty `dict`.
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
You tried to retrieve an item from `d` which is an empty `dict`.
Exception raised on line 8 of file TESTS:\runtime\test_key_error.py.
6: d = {}
7: try:
--> 8: d.popitem()
9: except KeyError as e:
d: {}
d.popitem: <builtin method popitem of dict object>
Similar names¶
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 145, in test_Similar_names
a = second["alpha"]
KeyError: 'alpha'
Did you mean `'alpha0'`?
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
The key `'alpha'` cannot be found in the dict `second`.
`second` has some keys similar to `'alpha'` including:
`'alpha0', 'alpha12', 'alpha11'`.
Exception raised on line 145 of file TESTS:\runtime\test_key_error.py.
143: second = {"alpha0": 1, "alpha11": 2, "alpha12": 3}
144: try:
-->145: a = second["alpha"]
^^^^^^^^^^^^^^^
146: except KeyError as e:
second: {'alpha0': 1, 'alpha11': 2, 'alpha12': 3}
String by mistake¶
Traceback (most recent call last):
File "TESTS:\runtime\test_key_error.py", line 98, in test_String_by_mistake
d["(0, 0)"]
KeyError: '(0, 0)'
Did you convert `(0, 0)` into a string by mistake?
A `KeyError` is raised when a value is not found as a
key in a Python dict or in a similar object.
The key `'(0, 0)'` cannot be found in the dict `d`.
`'(0, 0)'` is a string.
There is a key of `d` whose string representation
is identical to `'(0, 0)'`.
Exception raised on line 98 of file TESTS:\runtime\test_key_error.py.
96: d = {(0, 0): "origin"}
97: try:
--> 98: d["(0, 0)"]
99: except KeyError as e:
d: {(0, 0): 'origin'}
LookupError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_lookup_error.py", line 10, in test_Generic
raise LookupError("Fake message")
LookupError: Fake message
`LookupError` is the base class for the exceptions that are raised
when a key or index used on a mapping or sequence is invalid.
It can also be raised directly by codecs.lookup().
Exception raised on line 10 of file TESTS:\runtime\test_lookup_error.py.
8: # other than possibly codecs.lookup(), which is why we raise
9: # it directly here for our example.
-->10: raise LookupError("Fake message")
11: except LookupError as e:
LookupError: <class LookupError>
ModuleNotFoundError¶
Need to install module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 76, in test_Need_to_install_module
import alphabet
ModuleNotFoundError: No module named 'alphabet'
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
No module named `alphabet` can be imported.
Perhaps you need to install it.
Exception raised on line 76 of file TESTS:\runtime\test_module_not_found_error.py.
74: def test_Need_to_install_module():
75: try:
-->76: import alphabet
77: except ModuleNotFoundError as e:
Not a package¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 22, in test_Not_a_package
import os.xxx
ModuleNotFoundError: No module named 'os.xxx'; 'os' is not a package
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
`xxx` cannot be imported from `os`.
Exception raised on line 22 of file TESTS:\runtime\test_module_not_found_error.py.
20:
21: try:
-->22: import os.xxx
23: except ModuleNotFoundError as e:
Not a package similar name¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 36, in test_Not_a_package_similar_name
import os.pathh
ModuleNotFoundError: No module named 'os.pathh'; 'os' is not a package
Did you mean `import os.path`?
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
Perhaps you meant `import os.path`.
`path` is a name similar to `pathh` and is a module that
can be imported from `os`.
Other objects with similar names that are part of
`os` include `fspath`.
Exception raised on line 36 of file TESTS:\runtime\test_module_not_found_error.py.
34: def test_Not_a_package_similar_name():
35: try:
-->36: import os.pathh
37: except ModuleNotFoundError as e:
Object not module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 49, in test_Object_not_module
import os.open
ModuleNotFoundError: No module named 'os.open'; 'os' is not a package
Did you mean `from os import open`?
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
`open` is not a separate module but an object that is part of `os`.
Exception raised on line 49 of file TESTS:\runtime\test_module_not_found_error.py.
47: def test_Object_not_module():
48: try:
-->49: import os.open
50: except ModuleNotFoundError as e:
open: <builtin function open>
Similar object not module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 62, in test_Similar_object_not_module
import os.opend
ModuleNotFoundError: No module named 'os.opend'; 'os' is not a package
Did you mean `from os import open`?
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
Perhaps you meant `from os import open`.
`open` is a name similar to `opend` and is an object that
can be imported from `os`.
Other objects with similar names that are part of
`os` include `popen, fdopen`.
Exception raised on line 62 of file TESTS:\runtime\test_module_not_found_error.py.
60: def test_Similar_object_not_module():
61: try:
-->62: import os.opend
63: except ModuleNotFoundError as e:
Standard library module¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 7, in test_Standard_library_module
import Tkinter
ModuleNotFoundError: No module named 'Tkinter'
Did you mean `tkinter`?
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
No module named `Tkinter` can be imported.
Perhaps you need to install it.
`tkinter` is an existing module that has a similar name.
Exception raised on line 7 of file TESTS:\runtime\test_module_not_found_error.py.
5: def test_Standard_library_module():
6: try:
-->7: import Tkinter
8: except ModuleNotFoundError as e:
no curses¶
Traceback (most recent call last):
File "TESTS:\runtime\test_module_not_found_error.py", line 92, in test_no_curses
import curses
File "PYTHON_LIB:\curses\__init__.py", line 13, in <module>
from _curses import *
ModuleNotFoundError: No module named '_curses'
The curses module is rarely installed with Python on Windows.
A `ModuleNotFoundError` exception indicates that you
are trying to import a module that cannot be found by Python.
This could be because you misspelled the name of the module
or because it is not installed on your computer.
You have tried to import the curses module.
The curses module is rarely installed with Python on Windows.
Execution stopped on line 92 of file TESTS:\runtime\test_module_not_found_error.py.
90: def test_no_curses():
91: try:
-->92: import curses
93: except ModuleNotFoundError as e:
Exception raised on line 13 of file PYTHON_LIB:\curses\__init__.py.
11: """
12:
-->13: from _curses import *
14: import os as _os
NameError¶
Annotated variable¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 24, in test_Annotated_variable
y = x
NameError: name 'x' is not defined
Did you use a colon instead of an equal sign?
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
In your program, no object with the name `x` exists.
A type hint found for `x` in the global scope.
Perhaps you had used a colon instead of an equal sign and wrote
x : 3
instead of
x = 3
Exception raised on line 24 of file TESTS:\runtime\test_name_error.py.
22: def test_Annotated_variable():
23: try:
-->24: y = x
^
25: except NameError as e:
Custom name¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 163, in test_Custom_name
python
NameError: name 'python' is not defined
You are already using Python!
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
You are already using Python!
Exception raised on line 163 of file TESTS:\runtime\test_name_error.py.
161: def test_Custom_name():
162: try:
-->163: python
^^^^^^
164: except NameError as e:
Free variable referenced¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 149, in test_Free_variable_referenced
outer()
File "TESTS:\runtime\test_name_error.py", line 145, in outer
inner()
File "TESTS:\runtime\test_name_error.py", line 144, in inner
return var
NameError: free variable 'var' referenced before assignment in enclosing scope
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
In your program, `var` is an unknown name
that exists in an enclosing scope,
but has not yet been assigned a value.
Execution stopped on line 149 of file TESTS:\runtime\test_name_error.py.
147:
148: try:
-->149: outer()
150: except NameError as e:
outer: <function outer> from test_Free_variable_referenced
Exception raised on line 144 of file TESTS:\runtime\test_name_error.py.
142: def outer():
143: def inner():
-->144: return var
^^^
145: inner()
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 9, in test_Generic
this = something
NameError: name 'something' is not defined
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
In your program, no object with the name `something` exists.
I have no additional information for you.
Exception raised on line 9 of file TESTS:\runtime\test_name_error.py.
7: def test_Generic():
8: try:
--> 9: this = something
^^^^^^^^^
10: except NameError as e:
Missing import¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 129, in test_Missing_import
unicodedata.something
NameError: name 'unicodedata' is not defined
Did you forget to import `unicodedata`?
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
The name `unicodedata` is not defined in your program.
Perhaps you forgot to import `unicodedata` which is found
in Python's standard library.
Exception raised on line 129 of file TESTS:\runtime\test_name_error.py.
127:
128: try:
-->129: unicodedata.something
^^^^^^^^^^^
130: except NameError as e:
Synonym¶
Traceback (most recent call last):
File "TESTS:\runtime\test_name_error.py", line 89, in test_Synonym
cost # wrote from math import * above
NameError: name 'cost' is not defined
Did you mean `cos`?
A `NameError` exception indicates that a variable or
function name is not known to Python.
Most often, this is because there is a spelling mistake.
However, sometimes it is because the name is used
before being defined or given a value.
In your program, no object with the name `cost` exists.
Instead of writing `cost`, perhaps you meant one of the following:
* Global scope: `cos`, `cosh`, `acos`
Exception raised on line 89 of file TESTS:\runtime\test_name_error.py.
87:
88: try:
-->89: cost # wrote from math import * above
^^^^
90: except NameError as e:
OsError¶
Urllib error¶
Traceback (most recent call last):
File "PYTHON_LIB:\urllib\request.py", line 1354, in do_open
... More lines not shown. ...
File "PYTHON_LIB:\socket.py", line 787, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
File "PYTHON_LIB:\socket.py", line 918, in getaddrinfo
for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno 11001] getaddrinfo failed
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "TESTS:\runtime\test_os_error.py", line 7, in test_Urllib_error
request.urlopen("http://does_not_exist")
... More lines not shown. ...
File "PYTHON_LIB:\urllib\request.py", line 1383, in http_open
return self.do_open(http.client.HTTPConnection, req)
File "PYTHON_LIB:\urllib\request.py", line 1357, in do_open
raise URLError(err)
URLError: <urlopen error [Errno 11001] getaddrinfo failed>
An exception of type `URLError` is a subclass of `OSError`.
An `OSError` exception is usually raised by the Operating System
to indicate that an operation is not allowed or that
a resource is not available.
I suspect that you are trying to connect to a server and
that a connection cannot be made.
If that is the case, check for typos in the URL
and check your internet connectivity.
Execution stopped on line 7 of file TESTS:\runtime\test_os_error.py.
5: from urllib import request, error
6: try:
-->7: request.urlopen("http://does_not_exist")
8: except error.URLError as e:
request: <module urllib.request> from PYTHON_LIB:\urllib\request.py
request.urlopen: <function urlopen>
Exception raised on line 1357 of file PYTHON_LIB:\urllib\request.py.
1355: encode_chunked=req.has_header('Transfer-encoding'))
1356: except OSError as err: # timeout error
-->1357: raise URLError(err)
1358: r = h.getresponse()
global URLError: <class urllib.error.URLError>
OverflowError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_overflow_error.py", line 6, in test_Generic
2.0 ** 1600
OverflowError: (34, 'Result too large')
An `OverflowError` is raised when the result of an arithmetic operation
is too large to be handled by the computer's processor.
Exception raised on line 6 of file TESTS:\runtime\test_overflow_error.py.
4: def test_Generic():
5: try:
-->6: 2.0 ** 1600
7: except OverflowError as e:
RecursionError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_recursion_error.py", line 8, in test_Generic
a()
... More lines not shown. ...
File "TESTS:\runtime\test_recursion_error.py", line 6, in a
return a()
File "TESTS:\runtime\test_recursion_error.py", line 6, in a
return a()
RecursionError: maximum recursion depth exceeded
A `RecursionError` is raised when a function calls itself,
directly or indirectly, too many times.
It almost always indicates that you made an error in your code
and that your program would never stop.
Execution stopped on line 8 of file TESTS:\runtime\test_recursion_error.py.
6: return a()
7: try:
--> 8: a()
9: except RecursionError as e:
a: <function a> from test_Generic
Exception raised on line 6 of file TESTS:\runtime\test_recursion_error.py.
4: def test_Generic():
5: def a():
-->6: return a()
^^^
7: try:
a: <function a> from test_Generic
TypeError¶
Bad type for unary operator¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 371, in test_Bad_type_for_unary_operator
a =+ "def"
TypeError: bad operand type for unary +: 'str'
Perhaps you meant to write `+=` instead of `=+`
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You tried to use the unary operator '+'
with the following type of object: a string (`str`).
This operation is not defined for this type of object.
Perhaps you meant to write `+=` instead of `=+`
Exception raised on line 371 of file TESTS:\runtime\test_type_error.py.
369: # fmt: off
370: a = "abc"
-->371: a =+ "def"
^^^^^^^
372: # fmt: on
Builtin has no len¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 780, in test_Builtin_has_no_len
len("Hello world".split)
TypeError: object of type 'builtin_function_or_method' has no len()
Did you forget to call `"Hello world".split`?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
I suspect that you forgot to add parentheses to call `"Hello world".split`.
You might have meant to write:
`len("Hello world".split())`
Exception raised on line 780 of file TESTS:\runtime\test_type_error.py.
778: def test_Builtin_has_no_len():
779: try:
-->780: len("Hello world".split)
781: except TypeError as e:
len: <builtin function len>
"Hello world".split: <builtin method split of str object>
Can only concatenate¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 37, in test_Can_only_concatenate
result = a_tuple + a_list
TypeError: can only concatenate tuple (not "list") to tuple
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You tried to concatenate (add) two different types of objects:
a `tuple` and a `list`.
Exception raised on line 37 of file TESTS:\runtime\test_type_error.py.
35: a_tuple = (1, 2, 3)
36: a_list = [1, 2, 3]
-->37: result = a_tuple + a_list
^^^^^^^^^^^^^^^^
38: except TypeError as e:
a_list: [1, 2, 3]
a_tuple: (1, 2, 3)
Cannot convert dictionary update sequence¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 766, in test_Cannot_convert_dictionary_update_sequence
dd.update([1, 2, 3])
TypeError: cannot convert dictionary update sequence element #0 to a sequence
Perhaps you need to use the `dict.fromkeys()` method.
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
`dict.update()` does not accept a sequence as an argument.
Instead of writing `dd.update([1, 2, 3])`
perhaps you should use the `dict.fromkeys()` method: `dd.update( dict.fromkeys([1, 2, 3]) )`.
Exception raised on line 766 of file TESTS:\runtime\test_type_error.py.
764: dd = {"a": "a"}
765: try:
-->766: dd.update([1, 2, 3])
767: except TypeError as e:
dd: {'a': 'a'}
dd.update: <builtin method update of dict object>
Cannot multiply by non int¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 570, in test_Cannot_multiply_by_non_int
"a" * "2"
TypeError: can't multiply sequence by non-int of type 'str'
Did you forget to convert `"2"` into an integer?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You can only multiply sequences, such as list, tuples,
strings, etc., by integers.
Perhaps you forgot to convert `"2"` into an integer.
Exception raised on line 570 of file TESTS:\runtime\test_type_error.py.
568:
569: try:
-->570: "a" * "2"
571: except TypeError as e:
Cannot unpack non iterable object¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 738, in test_Cannot_unpack_non_iterable_object
a, b = 42.0
TypeError: cannot unpack non-iterable float object
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
Unpacking is a convenient way to assign a name,
to each item of an iterable.
An iterable is an object capable of returning its members one at a time.
Python containers (`list, tuple, dict`, etc.) are iterables,
but not objects of type `float`.
Exception raised on line 738 of file TESTS:\runtime\test_type_error.py.
736: def test_Cannot_unpack_non_iterable_object():
737: try:
-->738: a, b = 42.0
739: except TypeError as e:
Comparison not supported¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 320, in test_Comparison_not_supported
b >= a
TypeError: '>=' not supported between instances of 'int' and 'str'
Did you forget to convert the string `a` into an integer (`int`)?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You tried to do an order comparison (>=)
between two incompatible types of objects:
an integer (`int`) and a string (`str`).
Perhaps you forgot to convert the string `a` into an integer (`int`).
Exception raised on line 320 of file TESTS:\runtime\test_type_error.py.
318: a = "2"
319: b = 42
-->320: b >= a
321: except TypeError as e:
a: '2'
b: 42
Derive from BaseException¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 513, in test_Derive_from_BaseException
raise "exception" # noqa
TypeError: exceptions must derive from BaseException
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
In Python 3, exceptions must be derived from BaseException.
Exception raised on line 513 of file TESTS:\runtime\test_type_error.py.
511: def test_Derive_from_BaseException():
512: try:
-->513: raise "exception" # noqa
514: except TypeError as e:
Indices must be integers or slices¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 652, in test_Indices_must_be_integers_or_slices
[1, 2, 3]["2"]
TypeError: list indices must be integers or slices, not str
Did you forget to convert `"2"` into an integer?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
In the expression `[1, 2, 3]["2"]`
what is included between the square brackets, `[...]`,
must be either an integer or a slice
(`start:stop` or `start:stop:step`)
and you have used a string (`str`) instead.
Perhaps you forgot to convert `"2"` into an integer.
Exception raised on line 652 of file TESTS:\runtime\test_type_error.py.
650:
651: try:
-->652: [1, 2, 3]["2"]
653: except TypeError as e:
Not an integer¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 615, in test_Not_an_integer
range(c, d)
TypeError: 'str' object cannot be interpreted as an integer
Did you forget to convert `c, d` into integers?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You wrote an object of type `str` where an integer was expected.
Perhaps you forgot to convert `c, d` into integers.
Exception raised on line 615 of file TESTS:\runtime\test_type_error.py.
613: c, d = "2", "3"
614: try:
-->615: range(c, d)
616: except TypeError as e:
c: '2'
d: '3'
range: <class range>
Not callable¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 500, in test_Not_callable
_ = [1, 2](a + b)
TypeError: 'list' object is not callable
Did you mean `[1, 2][a + b]`?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
Because of the surrounding parenthesis, `(a + b)`
is interpreted by Python as indicating a function call for
`[1, 2]`, which is an object of type `list`
which cannot be called.
However, `[1, 2]` is a sequence.
Perhaps you meant to use `[]` instead of `()` and write
`[1, 2][a + b]`
Exception raised on line 500 of file TESTS:\runtime\test_type_error.py.
498: try:
499: a, b = 3, 7
-->500: _ = [1, 2](a + b)
^^^^^^^^^^^^^
501: except TypeError as e:
a: 3
b: 7
a + b: 10
Object is not iterable¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 724, in test_Object_is_not_iterable
list(42)
TypeError: 'int' object is not iterable
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
An iterable is an object capable of returning its members one at a time.
Python containers (`list, tuple, dict`, etc.) are iterables.
An iterable is required here.
Exception raised on line 724 of file TESTS:\runtime\test_type_error.py.
722: def test_Object_is_not_iterable():
723: try:
-->724: list(42)
725: except TypeError as e:
list: <class list>
Object is not subscriptable¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 710, in test_Object_is_not_subscriptable
a = f[1]
TypeError: 'function' object is not subscriptable
Did you mean `f(1)`?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
Subscriptable objects are typically containers from which
you can retrieve item using the notation `[...]`.
Perhaps you meant to write `f(1)`.
Exception raised on line 710 of file TESTS:\runtime\test_type_error.py.
708:
709: try:
-->710: a = f[1]
^^^^
711: except TypeError as e:
f: <function f> from test_Object_is_not_subscriptable
Slice indices must be integers or None¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 666, in test_Slice_indices_must_be_integers_or_None
[1, 2, 3][1.0:2.0]
TypeError: slice indices must be integers or None or have an __index__ method
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
When using a slice to extract a range of elements
from a sequence, that is something like
`[start:stop]` or `[start:stop:step]`
each of `start`, `stop`, `step` must be either an integer, `None`,
or possibly some other object having an `__index__` method.
Exception raised on line 666 of file TESTS:\runtime\test_type_error.py.
664: def test_Slice_indices_must_be_integers_or_None():
665: try:
-->666: [1, 2, 3][1.0:2.0]
667: except TypeError as e:
Too few positional argument¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 441, in test_Too_few_positional_argument
fn(1)
TypeError: fn() missing 2 required positional arguments: 'b' and 'c'
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You apparently have called the function 'fn()' with
fewer positional arguments than it requires (2 missing).
Exception raised on line 441 of file TESTS:\runtime\test_type_error.py.
439:
440: try:
-->441: fn(1)
442: except TypeError as e:
fn: <function fn> from test_Too_few_positional_argument
Too many positional argument¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 422, in test_Too_many_positional_argument
A().f(1)
TypeError: f() takes 1 positional argument but 2 were given
Perhaps you forgot `self` when defining `f`.
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You apparently have called the function `f` with
2 positional argument(s) while it requires 1
such positional argument(s).
Perhaps you forgot `self` when defining `f`.
Exception raised on line 422 of file TESTS:\runtime\test_type_error.py.
420:
421: try:
-->422: A().f(1)
423: except TypeError as e:
A: <class A> from test_type_error.test_Too_many_positional_argument
Tuple no item assignment¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 389, in test_Tuple_no_item_assignment
a[0] = 0
TypeError: 'tuple' object does not support item assignment
Did you mean to use a list?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
In Python, some objects are known as immutable:
once defined, their value cannot be changed.
You tried change part of such an immutable object: a `tuple`,
most likely by using an indexing operation.
Perhaps you meant to use a list instead.
Exception raised on line 389 of file TESTS:\runtime\test_type_error.py.
387: a = (1, 2, 3)
388: try:
-->389: a[0] = 0
390: except TypeError as e:
a: (1, 2, 3)
a[0]: 1
Unhachable type¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 683, in test_Unhachable_type
{[1, 2]: 1}
TypeError: unhashable type: 'list'
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
Only hashable objects can be used
as elements of `set` or keys of `dict`.
Hashable objects are objects that do not change value
once they have been created.Instead of using a `list`, consider using a `tuple`.
Exception raised on line 683 of file TESTS:\runtime\test_type_error.py.
681: def test_Unhachable_type():
682: try:
-->683: {[1, 2]: 1}
684: except TypeError as e:
Unsupported operand types¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 283, in test_Unsupported_operand_types
a @= b
TypeError: unsupported operand type(s) for @=: 'str' and 'int'
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
You tried to use the operator @=
using two incompatible types of objects:
a string (`str`) and an integer (`int`).
This operator is normally used only
for multiplication of matrices.
Exception raised on line 283 of file TESTS:\runtime\test_type_error.py.
281: a = "a"
282: b = 2
-->283: a @= b
284: except TypeError as e:
a: 'a'
b: 2
function has no len¶
Traceback (most recent call last):
File "TESTS:\runtime\test_type_error.py", line 796, in test_function_has_no_len
len(bad)
TypeError: object of type 'function' has no len()
Did you forget to call `bad`?
A `TypeError` is usually caused by trying
to combine two incompatible types of objects,
by calling a function with the wrong type of object,
or by trying to do an operation not allowed on a given type of object.
I suspect that you forgot to add parentheses to call `bad`.
You might have meant to write:
`len(bad())`
Exception raised on line 796 of file TESTS:\runtime\test_type_error.py.
794: pass
795: try:
-->796: len(bad)
797: except TypeError as e:
bad: <function bad> from test_function_has_no_len
len: <builtin function len>
UnboundLocalError¶
Missing both¶
Traceback (most recent call last):
File "TESTS:\runtime\test_unbound_local_error.py", line 61, in test_Missing_both
outer_missing_both()
File "TESTS:\runtime\test_unbound_local_error.py", line 22, in outer_missing_both
inner()
File "TESTS:\runtime\test_unbound_local_error.py", line 21, in inner
spam_missing_both += 1
UnboundLocalError: local variable 'spam_missing_both' referenced before assignment
Did you forget to add either `global spam_missing_both` or
`nonlocal spam_missing_both`?
In Python, variables that are used inside a function are known as
local variables. Before they are used, they must be assigned a value.
A variable that is used before it is assigned a value is assumed to
be defined outside that function; it is known as a `global`
(or sometimes `nonlocal`) variable. You cannot assign a value to such
a global variable inside a function without first indicating to
Python that this is a global variable, otherwise you will see
an `UnboundLocalError`.
The name `spam_missing_both` exists in both the global and nonlocal scope.
This can be rather confusing and is not recommended.
Depending on which variable you wanted to refer to, you needed to add either
global spam_missing_both
or
nonlocal spam_missing_both
as the first line inside your function.
Execution stopped on line 61 of file TESTS:\runtime\test_unbound_local_error.py.
59: def test_Missing_both():
60: try:
-->61: outer_missing_both()
62: except UnboundLocalError as e:
global outer_missing_both: <function outer_missing_both>
Exception raised on line 21 of file TESTS:\runtime\test_unbound_local_error.py.
19: spam_missing_both = 2
20: def inner():
-->21: spam_missing_both += 1
22: inner()
global spam_missing_both: 1
Missing global¶
Traceback (most recent call last):
File "TESTS:\runtime\test_unbound_local_error.py", line 27, in test_Missing_global
outer_missing_global()
File "TESTS:\runtime\test_unbound_local_error.py", line 10, in outer_missing_global
inner()
File "TESTS:\runtime\test_unbound_local_error.py", line 9, in inner
spam_missing_global += 1
UnboundLocalError: local variable 'spam_missing_global' referenced before assignment
Did you forget to add `global spam_missing_global`?
In Python, variables that are used inside a function are known as
local variables. Before they are used, they must be assigned a value.
A variable that is used before it is assigned a value is assumed to
be defined outside that function; it is known as a `global`
(or sometimes `nonlocal`) variable. You cannot assign a value to such
a global variable inside a function without first indicating to
Python that this is a global variable, otherwise you will see
an `UnboundLocalError`.
The name `spam_missing_global` exists in the global scope.
Perhaps the statement
global spam_missing_global
should have been included as the first line inside your function.
Execution stopped on line 27 of file TESTS:\runtime\test_unbound_local_error.py.
25: def test_Missing_global():
26: try:
-->27: outer_missing_global()
28: except UnboundLocalError as e:
global outer_missing_global: <function outer_missing_global>
Exception raised on line 9 of file TESTS:\runtime\test_unbound_local_error.py.
7: def outer_missing_global():
8: def inner():
--> 9: spam_missing_global += 1
10: inner()
global spam_missing_global: 1
Missing nonlocal¶
Traceback (most recent call last):
File "TESTS:\runtime\test_unbound_local_error.py", line 44, in test_Missing_nonlocal
outer_missing_nonlocal()
File "TESTS:\runtime\test_unbound_local_error.py", line 16, in outer_missing_nonlocal
inner()
File "TESTS:\runtime\test_unbound_local_error.py", line 15, in inner
spam_missing_nonlocal += 1
UnboundLocalError: local variable 'spam_missing_nonlocal' referenced before assignment
Did you forget to add `nonlocal spam_missing_nonlocal`?
In Python, variables that are used inside a function are known as
local variables. Before they are used, they must be assigned a value.
A variable that is used before it is assigned a value is assumed to
be defined outside that function; it is known as a `global`
(or sometimes `nonlocal`) variable. You cannot assign a value to such
a global variable inside a function without first indicating to
Python that this is a global variable, otherwise you will see
an `UnboundLocalError`.
The name `spam_missing_nonlocal` exists in the nonlocal scope.
Perhaps the statement
nonlocal spam_missing_nonlocal
should have been included as the first line inside your function.
Execution stopped on line 44 of file TESTS:\runtime\test_unbound_local_error.py.
42: def test_Missing_nonlocal():
43: try:
-->44: outer_missing_nonlocal()
45: except UnboundLocalError as e:
global outer_missing_nonlocal: <function outer_missing_nonlocal>
Exception raised on line 15 of file TESTS:\runtime\test_unbound_local_error.py.
13: spam_missing_nonlocal = 1
14: def inner():
-->15: spam_missing_nonlocal += 1
16: inner()
Typo in local¶
Traceback (most recent call last):
File "TESTS:\runtime\test_unbound_local_error.py", line 97, in test_Typo_in_local
test2()
File "TESTS:\runtime\test_unbound_local_error.py", line 94, in test2
alpha3 += 1
UnboundLocalError: local variable 'alpha3' referenced before assignment
Did you mean `alpha2`?
In Python, variables that are used inside a function are known as
local variables. Before they are used, they must be assigned a value.
A variable that is used before it is assigned a value is assumed to
be defined outside that function; it is known as a `global`
(or sometimes `nonlocal`) variable. You cannot assign a value to such
a global variable inside a function without first indicating to
Python that this is a global variable, otherwise you will see
an `UnboundLocalError`.
Instead of writing `alpha3`, perhaps you meant one of the following:
* Local scope: `alpha2`, `alpha1`
Execution stopped on line 97 of file TESTS:\runtime\test_unbound_local_error.py.
95:
96: try:
-->97: test2()
98: except UnboundLocalError as e:
test2: <function test2> from test_Typo_in_local
Exception raised on line 94 of file TESTS:\runtime\test_unbound_local_error.py.
92: alpha1 = 1
93: alpha2 = 1
-->94: alpha3 += 1
UnknownError¶
Generic¶
Traceback (most recent call last):
File "TESTS:\runtime\test_unknown_error.py", line 12, in test_Generic
raise MyException("Some informative message about an unknown exception.")
MyException: Some informative message about an unknown exception.
No information is known about this exception.
Please report this example to https://github.com/aroberge/friendly/issues.
If you are using a REPL, use `www('bug')` to do so.
If you are using the Friendly console, use `www()` to
do an Internet search for this particular case.
Exception raised on line 12 of file TESTS:\runtime\test_unknown_error.py.
10: friendly_traceback.debug_helper.DEBUG = False
11: try:
-->12: raise MyException("Some informative message about an unknown exception.")
13: except Exception as e:
global MyException: <class test_unknown_error.MyException>
ValueError¶
Date invalid month¶
Traceback (most recent call last):
File "TESTS:\runtime\test_value_error.py", line 58, in test_Date_invalid_month
d = date(2021, 13, 1)
ValueError: month must be in 1..12
Did you specify an invalid month?
A `ValueError` indicates that a function or an operation
received an argument of the right type, but an inappropriate value.
I am guessing that you specify an invalid value for a month
in a `date` object. Valid values are integers, from 1 to 12.
Exception raised on line 58 of file TESTS:\runtime\test_value_error.py.
56: from datetime import date
57: try:
-->58: d = date(2021, 13, 1)
^^^^^^^^^^^^^^^^^
59: except ValueError as e:
date: <class datetime.date>
Not enough values to unpack¶
Traceback (most recent call last):
File "TESTS:\runtime\test_value_error.py", line 28, in test_Not_enough_values_to_unpack
a, b, c = d
ValueError: not enough values to unpack (expected 3, got 2)
A `ValueError` indicates that a function or an operation
received an argument of the right type, but an inappropriate value.
Unpacking is a convenient way to assign a name,
to each item of an iterable.
In this instance, there are more names (3)
than the length of the iterable, a string (`str`) of length 2.
Exception raised on line 28 of file TESTS:\runtime\test_value_error.py.
26: d = "ab"
27: try:
-->28: a, b, c = d
29: except ValueError as e:
d: 'ab'
Too many values to unpack¶
Traceback (most recent call last):
File "TESTS:\runtime\test_value_error.py", line 43, in test_Too_many_values_to_unpack
a, b = c
ValueError: too many values to unpack (expected 2)
A `ValueError` indicates that a function or an operation
received an argument of the right type, but an inappropriate value.
Unpacking is a convenient way to assign a name,
to each item of an iterable.
In this instance, there are fewer names (2)
than the length of the iterable, a `list` of length 3.
Exception raised on line 43 of file TESTS:\runtime\test_value_error.py.
41: c = [1, 2, 3]
42: try:
-->43: a, b = c
44: except ValueError as e:
c: [1, 2, 3]
ZeroDivisionError¶
Complex division¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 155, in test_Complex_division
1 / zero
ZeroDivisionError: complex division by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are dividing by the following term
zero
which is equal to zero.
Exception raised on line 155 of file TESTS:\runtime\test_zero_division_error.py.
153: zero = 0j
154: try:
-->155: 1 / zero
156: except ZeroDivisionError as e:
zero: 0j
Division by zero literal¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 199, in test_Division_by_zero_literal
1. / 0
ZeroDivisionError: float division by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are dividing by zero.
Exception raised on line 199 of file TESTS:\runtime\test_zero_division_error.py.
197:
198: try:
-->199: 1. / 0
200: except ZeroDivisionError as e:
Division operator¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 17, in test_Division_operator
1 / zero
ZeroDivisionError: division by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are dividing by the following term
zero
which is equal to zero.
Exception raised on line 17 of file TESTS:\runtime\test_zero_division_error.py.
15:
16: try:
-->17: 1 / zero
18: except ZeroDivisionError as e:
zero: 0
Divmod¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 82, in test_Divmod
divmod(1, zero)
ZeroDivisionError: integer division or modulo by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
The second argument of the `divmod()` function is zero.
Exception raised on line 82 of file TESTS:\runtime\test_zero_division_error.py.
80: zero = 0
81: try:
-->82: divmod(1, zero)
83: except ZeroDivisionError as e:
zero: 0
divmod: <builtin function divmod>
Float division¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 125, in test_Float_division
1 / zero
ZeroDivisionError: float division by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are dividing by the following term
zero
which is equal to zero.
Exception raised on line 125 of file TESTS:\runtime\test_zero_division_error.py.
123: zero = 0.
124: try:
-->125: 1 / zero
126: except ZeroDivisionError as e:
zero: 0.0
Float divmod¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 140, in test_Float_divmod
divmod(1, zero)
ZeroDivisionError: float divmod()
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
The second argument of the `divmod()` function is equal to zero.
Exception raised on line 140 of file TESTS:\runtime\test_zero_division_error.py.
138: zero = 0.
139: try:
-->140: divmod(1, zero)
141: except ZeroDivisionError as e:
zero: 0.0
divmod: <builtin function divmod>
Float modulo¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 110, in test_Float_modulo
1 % zero
ZeroDivisionError: float modulo
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
Using the modulo operator, you are dividing by the following term
zero
which is equal to zero.
Exception raised on line 110 of file TESTS:\runtime\test_zero_division_error.py.
108:
109: try:
-->110: 1 % zero
111: except ZeroDivisionError as e:
zero: 0.0
Integer division operator¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 42, in test_Integer_division_operator
1 // zero
ZeroDivisionError: integer division or modulo by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are dividing by the following term
zero
which is equal to zero.
Exception raised on line 42 of file TESTS:\runtime\test_zero_division_error.py.
40:
41: try:
-->42: 1 // zero
43: except ZeroDivisionError as e:
zero: 0
Mixed operations¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 212, in test_Mixed_operations
a = divmod(8, 1 // 2)
ZeroDivisionError: integer division or modulo by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
The following mathematical expression includes a division by zero:
divmod(8, 1 // 2)
Exception raised on line 212 of file TESTS:\runtime\test_zero_division_error.py.
210: def test_Mixed_operations():
211: try:
-->212: a = divmod(8, 1 // 2)
^^^^^^^^^^^^^^^^^
213: except ZeroDivisionError as e:
divmod: <builtin function divmod>
1 // 2: 0
Modulo operator¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 67, in test_Modulo_operator
1 % zero
ZeroDivisionError: integer division or modulo by zero
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
Using the modulo operator, you are dividing by the following term
zero
which is equal to zero.
Exception raised on line 67 of file TESTS:\runtime\test_zero_division_error.py.
65:
66: try:
-->67: 1 % zero
68: except ZeroDivisionError as e:
zero: 0
Raise zero negative power¶
Traceback (most recent call last):
File "TESTS:\runtime\test_zero_division_error.py", line 170, in test_Raise_zero_negative_power
zero ** -1
ZeroDivisionError: 0.0 cannot be raised to a negative power
A `ZeroDivisionError` occurs when you are attempting to divide a value
by zero either directly or by using some other mathematical operation.
You are attempting to raise the number 0 to a negative power
which is equivalent to dividing by zero.
Exception raised on line 170 of file TESTS:\runtime\test_zero_division_error.py.
168: zero = 0
169: try:
-->170: zero ** -1
171: except ZeroDivisionError as e:
zero: 0