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BUG: incompatible dtype when creating bool column with df.at #56600

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@charizard-knows

Description

@charizard-knows

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Reproducible Example

import pandas as pd

df = pd.DataFrame()
condition = [True, False, True, True]

for i in range(len(condition)):
    df.at[i,'truth'] = condition[i]

Issue Description

While making a column from a loop, I get an incompaitible dtype warning.

FutureWarning: Setting an item of incompatible dtype is deprecated and will raise in a future error of pandas. Value 'True' has dtype incompatible with float64, please explicitly cast to a compatible dtype first.
df.at[i,'truth'] = condition[i]

Pandas most probably complaints about casting to float64 because np.NaN is considered a float and pandas defaults to making a column filled with np.NaN

Expected Behavior

No warning

Installed Versions

INSTALLED VERSIONS

commit : a671b5a
python : 3.11.6.final.0
python-bits : 64
OS : Windows
OS-release : 10
Version : 10.0.19045
machine : AMD64
processor : AMD64 Family 23 Model 24 Stepping 1, AuthenticAMD
byteorder : little
LC_ALL : None
LANG : None
LOCALE : English_India.1252

pandas : 2.1.4
numpy : 1.26.2
pytz : 2023.3.post1
dateutil : 2.8.2
setuptools : 65.5.0
pip : 23.2.1
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 : 8.18.1
pandas_datareader : None
bs4 : 4.12.2
bottleneck : None
dataframe-api-compat: None
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : None
numba : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : None
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
zstandard : None
tzdata : 2023.3
qtpy : None
pyqt5 : None

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