pd.concat with names=None

[amgcc]

Describe the bug
pd.concat should accept names=None as it is the default value.

To Reproduce

1. Provide a minimal runnable pandas example that is not properly checked by the stubs.

def maybe_concat(
    dd: dict[str, pd.DataFrame], names: list[str] | None = None
) -> pd.DataFrame:
    """Concatenate a dict of dataframes if available."""
    return pd.concat(dd, names=names) if dd else pd.DataFrame()

2. Indicate which type checker you are using (mypy or pyright).
   mypy
3. Show the error message received from that type checker while checking your example.

error: Argument "names" to "concat" has incompatible type "list[str] | None"; expected "list[str]"  [arg-type]

Please complete the following information:

• OS: [e.g. Windows, Linux, MacOS] Linux
• OS Version [e.g. 22] Fedora 7
• python version 3.11.8
• version of type checker 1.8.0
• version of installed pandas-stubs 2.1.4

[Dr-Irv]

Yes, that's an error. Easy fix to add the | None to the names argument in pandas-stubs/core/reshape/concat.pyi PR with tests welcome.

[amgcc]

Ill try and tackle this.

[Aftabby]

Hello, @Dr-Irv
I'm assigning the issue to myself, as it seems no one else has done any improvement on it yet.

[Aftabby]

take

[Aftabby]

Hello @Dr-Irv ,
Will you kindly check if issue has been solved with #894 or not?