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raise-not-implemented (F901)#

Derived from the Pyflakes linter.

Fix is sometimes available.

What it does#

Checks for raise statements that raise NotImplemented.

Why is this bad?#

NotImplemented is an exception used by binary special methods to indicate that an operation is not implemented with respect to a particular type.

NotImplemented should not be raised directly. Instead, raise NotImplementedError, which is used to indicate that the method is abstract or not implemented in the derived class.


class Foo:
    def bar(self):
        raise NotImplemented

Use instead:

class Foo:
    def bar(self):
        raise NotImplementedError