DOC: Note itertuples created with rename=True

[snowman2]

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Reproducible Example

>>> import pandas
>>> pdf = pandas.DataFrame({"yield": [1, 2]})
>>> pdf
   yield
0      1
1      2
>>> item = next(pdf.itertuples())
>>> item
Pandas(Index=0, _1=1)

Issue Description

The column named "yield" is renamed in itertuples.

Expected Behavior

The column name remains unchanged.

Installed Versions

INSTALLED VERSIONS

commit : 8dab54d
python : 3.9.15.final.0
python-bits : 64
OS : Linux
OS-release : 5.15.0-58-generic
Version : #64-Ubuntu SMP Thu Jan 5 11:43:13 UTC 2023
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.5.2
numpy : 1.23.5
pytz : 2022.7.1
dateutil : 2.8.2
setuptools : 66.0.0
pip : 22.3.1
Cython : None
pytest : 7.2.1
hypothesis : None
sphinx : 5.3.0
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : 2.9.3
jinja2 : 3.1.2
IPython : 8.8.0
pandas_datareader: None
bs4 : 4.11.1
bottleneck : 1.3.5
brotli :
fastparquet : None
fsspec : 2022.11.0
gcsfs : None
matplotlib : 3.6.2
numba : 0.56.4
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 9.0.0
pyreadstat : None
pyxlsb : None
s3fs : 2022.11.0
scipy : 1.10.0
snappy : None
sqlalchemy : 1.4.46
tables : None
tabulate : 0.9.0
xarray : 2022.12.0
xlrd : None
xlwt : None
zstandard : None
tzdata : 2022.7

[mroeschke]

This is as intended as the namedtuples are generated with rename=True: https://docs.python.org/3/library/collections.html#collections.namedtuple

And this is tested in test_itertuples

This could be better documented

[mroeschke]

Oh actually this is documented in the docstring

https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.itertuples.html

The column names will be renamed to positional names if they are invalid Python identifiers, repeated, or start with an underscore.

Therefore closing

[snowman2]

Thanks 👍

[snowman2]

Might not be bad to add a reference to this: https://realpython.com/python-keywords/

[snowman2]

Or at least this: https://docs.python.org/3/library/keyword.html