Skip to content

unused-private-type-alias (PYI047)

Derived from the flake8-pyi linter.

What it does

Checks for the presence of unused private type aliases.

Why is this bad?

A private type alias that is defined but not used is likely a mistake. It should either be used, made public, or removed to avoid confusion.

Example

import typing

_UnusedTypeAlias: typing.TypeAlias = int

Use instead:

import typing

_UsedTypeAlias: typing.TypeAlias = int

def func(arg: _UsedTypeAlias) -> _UsedTypeAlias: ...