Union type of two concrete modules is ModuleType #22302

Bug Report

It’s #11085, but that one was closed as a duplicate of an unrelated bug, so I’m filing the actual one again

To Reproduce

import json
import pickle


def f(flag: bool) -> None:
    mod = json if flag else pickle
    reveal_type(mod)        # types.ModuleType
    reveal_type(mod.dumps)  # Any
    mod.does_not_exist      # no error

Expected Behavior

Creates a union of two concrete module types

Actual Behavior

Loses all type information about the modules

Your Environment

• Mypy version used: 2.4.0 (compiled: yes)
• Mypy command-line flags: none (mypy r.py)
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: 3.14.7