ENH: set __module__ on isna and notna

[SiemBerhane]

• Part of ENH: set __module__ on top-level public objects #55178 (Replace xxxx with the GitHub issue number)
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.
• Added type annotations to new arguments/methods/functions.
• Added an entry in the latest doc/source/whatsnew/vX.X.X.rst file if fixing a bug or adding a new feature.

[chanshing]

pd.notna is top-level too and is defined in missing.py, so maybe could be included in this PR

pandas/pandas/core/dtypes/missing.py

Line 316 in 217a0ed

def notna(obj: object) -> bool | npt.NDArray[np.bool_] | NDFrame:

[simonjayhawkins]

Thanks @SiemBerhane

[SiemBerhane]

Thanks @SiemBerhane

Glad it finally works. Thanks for your help!

[jorisvandenbossche]

Thanks, looks good!

Because of merging some of the related PRs, there is now a merge conflict in the tests file. Could you merge the latest main to resolve that conflict? (and let us know if you need any help with that)

[simonjayhawkins]

@jorisvandenbossche

isnull and notnull are aliases to isna and notna respectively that are also defined in pandas/core/dtypes/missing.py

now the documentation for isnull is the same as isna (because it's just an alias to isna).

should the docs additionally mention that is an alias? are isnull and notnull recommended uses?

in IPython the repr now for pd.isnull is <function pandas.isna(obj: 'object') -> 'bool | npt.NDArray[np.bool_] | NDFrame'>. While we're improving the output formatting is there any value in making this show <function pandas.isnull.... instead?

would we also want an assert in the tests for pd.isnull and pd.notnull too?

[jorisvandenbossche]

isnull and notnull are aliases to isna and notna respectively that are also defined in pandas/core/dtypes/missing.py

I think for those aliases it is fine that the repr points to the isna/notna instead (I mean, I wouldn't do specific effort to fix that, although addressing the docstring might also address this).

Ideally those docstrings of isnull/notnull should mention they are aliases, though