BUG: cannot replace np.NaN with None any more

[sorenwacker]

Pandas version checks

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

Reproducible Example

import pandas as pd
import numpy as np

pd.DataFrame({'A': [np.NaN]}).replace(np.NaN, None)
> RecursionError: maximum recursion depth exceeded while calling a Python object

Issue Description

This was working in an earlier versoin of pandas, but not in 1.5.1 any more.

Expected Behavior

The np.NaNs should be replaced with None in the current dataframe.

Installed Versions

INSTALLED VERSIONS

commit : 91111fd
python : 3.9.15.final.0
python-bits : 64
OS : Linux
OS-release : 5.4.0-135-generic
Version : #152-Ubuntu SMP Wed Nov 23 20:19:22 UTC 2022
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.5.1
numpy : 1.21.5
pytz : 2022.1
dateutil : 2.8.2
setuptools : 65.5.0
pip : 22.2.2
Cython : None
pytest : 6.2.5
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : 3.0.2
lxml.etree : 4.6.4
html5lib : None
pymysql : None
psycopg2 : 2.9.5
jinja2 : 3.0.3
IPython : 8.6.0
pandas_datareader: None
bs4 : 4.10.0
bottleneck : 1.3.5
brotli :
fastparquet : 0.7.1
fsspec : 2021.11.0
gcsfs : None
matplotlib : 3.6.1
numba : 0.55.1
numexpr : 2.8.3
odfpy : None
openpyxl : 3.0.9
pandas_gbq : None
pyarrow : 6.0.0
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.6.2
snappy : None
sqlalchemy : 1.4.27
tables : 3.6.1
tabulate : 0.8.9
xarray : None
xlrd : 2.0.1
xlwt : None
zstandard : None
tzdata : None

[mroeschke]

I believe this is fixed if you install 1.5.2 https://pandas.pydata.org/docs/dev/whatsnew/v1.5.2.html

[sorenwacker]

Confirmed. For some reason my conda update pandas did not update pandas accordingly.
Thanks