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builtin-argument-shadowing (A002)#

Derived from the flake8-builtins linter.

What it does#

Checks for any function arguments that use the same name as a builtin.

Why is this bad?#

Reusing a builtin name for the name of an argument increases the difficulty of reading and maintaining the code, and can cause non-obvious errors, as readers may mistake the argument for the builtin and vice versa.

Builtins can be marked as exceptions to this rule via the flake8-builtins.builtins-ignorelist configuration option.

Example#

def remove_duplicates(list, list2):
    result = set()
    for value in list:
        result.add(value)
    for value in list2:
        result.add(value)
    return list(result)  # TypeError: 'list' object is not callable

Use instead: 

def remove_duplicates(list1, list2):
    result = set()
    for value in list1:
        result.add(value)
    for value in list2:
        result.add(value)
    return list(result)

Options#

References#