Wrong typing for the values argument of the pandas.DataFrame.pivot_table method

[airatk]

Describe the bug
The values argument of the pandas.DataFrame.pivot_table method has type of str | None:

pandas-stubs/pandas-stubs/core/frame.pyi

Lines 1126 to 1137 in 7dd7b6a

	def pivot_table(
	self,
	values: _str | None = ...,
	index: _str | Grouper | Sequence | None = ...,
	columns: _str | Grouper | Sequence | None = ...,
	aggfunc=...,
	fill_value: Scalar | None = ...,
	margins: _bool = ...,
	dropna: _bool = ...,
	margins_name: _str = ...,
	observed: _bool = ...,
	) -> DataFrame: ...

But the Pandas documentation says that values may have not only a string value, but also a list-like value:
Docs of pandas.DataFrame.pivot_table

To Reproduce

1. A minimal runnable pandas example that is not properly checked by the stubs:

from pandas import DataFrame

data_frame = DataFrame({
    'a': [1, 2],
    'b': [1, 2],
    'c': [1, 2],
    'd': [1, 2],
})
data_frame.pivot_table(
    values=['a', 'b'],
    index=['c', 'd'],
)

3. I am using mypy.
4. The error message received from mypy:

error: Argument "values" to "pivot_table" of "DataFrame" has incompatible type "list[str]"; expected "str | None"  [arg-type]
Found 1 error in 1 file (checked 80 source files)

Please complete the following information:

• OS: Ubuntu
• OS version: 23.10
• python version: 3.10.11
• mypy version: 1.8.0
• pandas-stubs version: 2.2.0.240218

[Dr-Irv]

Thanks for the report. As you pointed out, it's a simple fix to add a Sequence[_str] to the values argument in the stub

PR with test welcome

[Aftabby]

Hi @Dr-Irv ,

I noticed that this issue is currently unassigned, and I'm interested in working on it. Could you please assign it to me? I believe I can contribute to fix the problem (as per you mentioned).

Thanks.

[Dr-Irv]

I noticed that this issue is currently unassigned, and I'm interested in working on it. Could you please assign it to me? I believe I can contribute to fix the problem (as per you mentioned).

Assigned to you. Be sure to update the stub and include a test

[Aftabby]

I noticed that this issue is currently unassigned, and I'm interested in working on it. Could you please assign it to me? I believe I can contribute to fix the problem (as per you mentioned).

Assigned to you. Be sure to update the stub and include a test

It seems there is already a test exists regarding this issue #885

    check(
        assert_type(
            df.pivot(index="col1", columns="col3", values=["col2", "col4"]),
            pd.DataFrame,
        ),
        pd.DataFrame,
    )

Should I include another one of the same kind?

[Dr-Irv]

Should I include another one of the same kind?

Possibly, but the check you included tests DataFrame.pivot(), and for this issue, it needs to be a check on DataFrame.pivot_table()