Since 1.6.0 TypeVar with bound types fails to match with Callable of the same bound types

Bug Report

Did not occur prior to 1.6.0.

https://github.com/python-cmd2/cmd2/actions/runs/6699406223/job/18203570049
Got the following error with mypy:

cmd2/cmd2.py: note: In member "_build_parser" of class "Cmd":
cmd2/cmd2.py:699:46: error: Argument 1 has incompatible type "CommandParent"; expected "Union[Type[Cmd], Type[CommandSet]]"  [arg-type]
Found 1 error in 1 file (checked 18 source files)

where CommandParent is a TypeVar declared as:

CommandParent = TypeVar('CommandParent', bound=Union['cmd2.Cmd', CommandSet])

To Reproduce

https://github.com/python-cmd2/cmd2/blob/8d88c357ca0764b114c68d8175d2cd33146b83d7/cmd2/cmd2.py#L694

Expected Behavior

Since CommandParent is bound to the expected type, this shouldn't be an error

Actual Behavior

I get the error above.

Your Environment

• Mypy version used: 1.6.1
• Mypy command-line flags:
• Mypy configuration options from mypy.ini (and other config files):
• Python version used: 3.8, 3.9,3.10,3.11

Riproduci il malfunzionamento di cmd2/cmd2.py intorno alla riga 694 usando mypy 1.6.1 e le versioni di Python indicate. Confronta il bound di TypeVar con la gestione degli argomenti di Callable, quindi verifica che i tipi compatibili indicati non producano più l’errore arg-type.