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raise-not-implemented (F901)

Added in v0.0.18 · Related issues · View source

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.

Example

class Foo:
    def bar(self):
        raise NotImplemented

Use instead:

class Foo:
    def bar(self):
        raise NotImplementedError

References