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Mypy complains about inconsistent MRO when using `isinstance()` on a generic `Series` object

See original GitHub issue

To Reproduce

import pandas as pd

x: pd.Series[int] = pd.Series([1, 3, 4], name="my series")
assert isinstance(x, pd.Series)  # this line produces the error below

mypy gives the following error:

repro.py:4: error: Subclass of "Series[int]" and "TimestampSeries" cannot exist: would have inconsistent method resolution order  [unreachable]

pyright does not complain. Nor does mypy complain if I drop the [int] for pd.Series.

Please complete the following information:

OS: Linux
OS Version: Ubuntu 22.04
python version: 3.10.4
version of type checker: mypy 0.971
version of installed pandas-stubs: 1.4.3.220829

Issue Analytics

State:
Created a year ago
Comments:12 (6 by maintainers)

Top GitHub Comments

1reaction

thomkehcommented, Oct 6, 2022

I reported it here: https://github.com/python/mypy/issues/13824

0reactions

Dr-Irvcommented, Nov 20, 2022

Bug still exists in mypy 0.990

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