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Calling type[T] returns the parent of T on Python 3.12+ #18088

@Avasam

Description

@Avasam

Bug Report / To Reproduce
Ok so this is a weird one, and I've been completely unable to replicate it in an MRE. So here's the PR where this happened to us: pypa/setuptools#4726

To replicate, clone the setuptools repo, install the [core,type] extras, then change the start of setuptools/command/install.py's install.do_egg_install to:

    def do_egg_install(self) -> None:
        easy_install = cast(
            type[easy_install_cls], self.distribution.get_command_class('easy_install')
        )

        cmd = easy_install(
            self.distribution,
            args="x",
            root=self.root,
            record=self.record,
        )
        reveal_type(cmd)

On Python 3.11

setuptools\command\install.py:150: note: Revealed type is "setuptools.command.easy_install.easy_install"
Success: no issues found in 143 source files

On Python 3.12 & 3.13

setuptools\command\install.py:150: note: Revealed type is "setuptools.Command"
setuptools\command\install.py:166: error: Unexpected keyword argument "show_deprecation" for "run" of "Command"  [call-arg]
Found 1 error in 1 file (checked 143 source files)

My first guess is this has something to do with distutils removal in 3.12, but the results I'm getting are still nonsensical and probably reveal a hidden bug in mypy.

Expected Behavior
cmd should be of type setuptools.command.easy_install or alias easy_install_cls

Actual Behavior

cmd is of type setuptools.Command (superclass of setuptools.command.easy_install)

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