BUG: Regression - AmbiguousTimeError creating DataFrame · Issue #42505 · pandas-dev/pandas (original) (raw)

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Code Sample, a copy-pastable example

Pandas 1.25:

import pandas as pd dt = pd.to_datetime('2019-11-03 01:00:00-0700').tz_convert('America/Los_Angeles') pd.DataFrame({'dt': dt, 'value': [1]})

dt value

0 2019-11-03 01:00:00-07:00 1

Pandas 1.3:

import pandas as pd dt = pd.to_datetime('2019-11-03 01:00:00-0700').tz_convert('America/Los_Angeles') pd.DataFrame({'dt': dt, 'value': [1]})

File "pandas/_libs/tslibs/tzconversion.pyx", line 284, in pandas._libs.tslibs.tzconversion.tz_localize_to_utc

pytz.exceptions.AmbiguousTimeError: Cannot infer dst time from 2019-11-03 01:00:00, try using the 'ambiguous' argument

Problem description

The dt object already has a timezone attribute, so it shouldn't be converting/inferring at all.

Expected Output

1.25 and 1.3.0 should have the same output.

Output of pd.show_versions()

INSTALLED VERSIONS

commit : f00ed8f
python : 3.7.3.final.0
python-bits : 64
OS : Darwin
OS-release : 20.5.0
Version : Darwin Kernel Version 20.5.0: Sat May 8 05:10:33 PDT 2021; root:xnu-7195.121.3~9/RELEASE_X86_64
machine : x86_64
processor : i386
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.3.0
numpy : 1.21.0
pytz : 2021.1
dateutil : 2.8.1
pip : 21.1.2
setuptools : 57.0.0
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : 2.9.1 (dt dec pq3 ext lo64)
jinja2 : None
IPython : None
pandas_datareader: None
bs4 : None
bottleneck : None
fsspec : None
fastparquet : None
gcsfs : None
matplotlib : 3.2.2
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyxlsb : None
s3fs : None
scipy : 1.7.0
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
numba : None