BUG: register_dataframe_accessor causes "Untyped class decorator obscures type of class; ignoring decorator"

[davetapley]

Pandas version checks

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• I have confirmed this bug exists on the latest version of pandas.

• I have confirmed this bug exists on the main branch of pandas.

Reproducible Example

@pd.api.extensions.register_dataframe_accessor("geo")
class GeoAccessor:
    ...

Issue Description

Example from the docs causes:

Untyped class decorator obscures type of class; ignoring decoratorPylance[reportUntypedClassDecorator](https://github.com/microsoft/pyright/blob/main/docs/configuration.md#reportUntypedClassDecorator)

in VSCode.

Expected Behavior

No error.

Installed Versions

INSTALLED VERSIONS

commit : 4fe49b1
python : 3.11.7.final.0
python-bits : 64
OS : Linux
OS-release : 6.2.0-1019-azure
Version : #19~22.04.1-Ubuntu SMP Wed Jan 10 22:57:03 UTC 2024
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : C.UTF-8
LOCALE : en_US.UTF-8

pandas : 3.0.0.dev0+706.g4fe49b160e
numpy : 1.26.4
pytz : 2024.1
dateutil : 2.9.0.post0
setuptools : 69.0.3
pip : 24.0
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.1.2
IPython : None
pandas_datareader : None
adbc-driver-postgresql: None
adbc-driver-sqlite : None
bs4 : None
bottleneck : None
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : None
numba : None
numexpr : None
odfpy : None
openpyxl : None
pyarrow : 14.0.1
pyreadstat : None
python-calamine : None
pyxlsb : None
s3fs : None
scipy : 1.10.1
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
zstandard : None
tzdata : 2024.1
qtpy : None

[davetapley]

See also:

• TYP: Make better type hints for using register_dataframe_accessor #50206
• Untyped Class Decorator while reveal type disagrees microsoft/pyright#2773 (I suspect this is cause)