Cannot instantiate Type[Type[...]]

Bug Report

Mypy thinks that Type[Type[...]] cannot be instantiated. I understand that it can be difficult to support, but is there any reason to consider it an error?

Type[Type[something]] is type or its subclass. It can be instantiated (code below runs without errors).

To Reproduce

Write the following code, run mypy on it.

class A:
    pass

B = type(A)('B', (A,), {})
b = B()

Playground

Expected Behavior

No errors (but I'm not sure that I'm not just missing something and under certain circumstances such code can be incorrect).

Actual Behavior

mypy reports:

main.py:4: error: Cannot instantiate type "Type[Type[A]]"

Your Environment

• Mypy version used: 0.941 latest (from pip & playground)
• Mypy command-line flags: nothing
• Mypy configuration options from mypy.ini (and other config files): nothing
• Python version used: 3.10
• Operating system and version: Ubuntu 22.04

まず、報告されているクラス定義と type() の呼び出しを main.py に配置し、指定された Python 3.10 のセットアップで mypy を実行して診断を再現します。Type[Type[A]] の処理を追跡し、このケースを対象とするリグレッションテストを追加します。mypy がこの例を受け入れ、無関係なインスタンス化チェックを弱めていなければ完了です。