pd.read_excel() has some parameters incorrectly documented

[Dr-Irv]

Environment data

• Language Server version: 2020.9.5
• OS and version: Windows 10
• Python version (& distribution if applicable, e.g. Anaconda): Anaconda 3.7.5

Code Snippet / Additional information

The stubs for read_excel have some errors with respect to the header and skiprows arguments. The following diffs in the file dist/bundled-stubs/pandas/io/excel/_base.pyi fix these issues:

diff _base.pyi.ORIG _base.pyi
10c10
<     header: Union[int, Sequence[int]] = ...,
---
>     header: Optional[Union[int, Sequence[int]]] = ...,
20c20
<     skiprows: Optional[Sequence[int]] = ...,
---
>     skiprows: Optional[Union[Sequence[int], int, Callable]] = ...,
271c271
<     header: Union[int, Sequence[int]] = ...,
---
>     header: Optional[Union[int, Sequence[int]]] = ...,
281c281
<     skiprows: Optional[Sequence[int]] = ...,
---
>     skiprows: Optional[Union[Sequence[int], int, Callable]] = ...,

Details on why these changes are needed:

1. For header, the value None is allowed
2. For skiprows, the docs need to be updated. See DOC: read_excel supports skiprows argument like read_csv, but tests and docs needed pandas-dev/pandas#36435

[Dr-Irv]

Note - when I first reported this, I thought that sheetname was wrong, but now I see what the @overload is doing, so all is well. Updated the original text above to remove that part.

[gramster]

For skiprows, this is motivation to start making PRs against pandas to inline these types or we'll be whacking moles endlessly.

[jakebailey]

This issue has been fixed in version 2020.9.6, which we've just released. You can find the changelog here: https://github.com/microsoft/pylance-release/blob/master/CHANGELOG.md#202096-23-september-2020