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invalid-first-argument-name-for-class-method (N804)#

Derived from the pep8-naming linter.

Fix is sometimes available.

What it does#

Checks for class methods that use a name other than cls for their first argument.

Why is this bad?#

PEP 8 recommends the use of cls as the first argument for all class methods:

Always use cls for the first argument to class methods.

If a function argument’s name clashes with a reserved keyword, it is generally better to append a single trailing underscore rather than use an abbreviation or spelling corruption. Thus class_ is better than clss. (Perhaps better is to avoid such clashes by using a synonym.)

Names can be excluded from this rule using the lint.pep8-naming.ignore-names or lint.pep8-naming.extend-ignore-names configuration options. For example, to allow the use of klass as the first argument to class methods, set the lint.pep8-naming.extend-ignore-names option to ["klass"].


class Example:
    def function(self, data):

Use instead:

class Example:
    def function(cls, data):

Fix safety#

This rule's fix is marked as unsafe, as renaming a method parameter can change the behavior of the program.