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There is a newer version: 4.23.0.17664

This rule raises an issue when a type alias is declared outside of a type statement.
Why is this an issue?
Since Python 3.12 the keyword type is used to defined type aliases. It replaces the following construct:
from typing import TypeAlias, TypeVar

_T = TypeVar("_T")

MyTypeAlias: TypeAlias = set[_T]

Using the type statement to define type aliases allows for a more concise code and thus better readability. This also makes it
possible to declutter the code, as imports from the typing module (TypeAlias and TyperVar) can be removed.
type MyTypeAlias[T] = set[T]

Exceptions
This rule will only raise an issue when the Python version of the analyzed project is set to 3.12 or higher.
How to fix it
Use a type statement to declare the TypeAlias instead of using a regular assignment.
Code examples
Noncompliant code example
from typing import TypeAlias

MyStringAlias: TypeAlias = str # Noncompliant: this TypeAlias can be more concise with the help of the type statement.

_T = TypeVar("_T")
MyGenericAlias: TypeAlias = list[_T]  # Noncompliant: the type statement can help replace both the TypeVar and the TypeAlias statements.

Compliant solution
type MyStringAlias = str # Compliant

type MyGenericAlias[T] = list[T]  # Compliant

Resources
Documentation

   Python Documentation - The type statement 
   Python 3.12 Release Notes - PEP 695: Type Parameter
  Syntax