Cannot import due to ModuleNotFound 'pytz'

[scizorman]

Environment details

• OS type and version: Ubuntu 20.04
• Python version: Python 3.9.6
• pip version: pip 21.2.4
• google-cloud-bigquery version: 2.24.0

Steps to reproduce

1. pip install 'google-cloud-bigquery==2.24.0'
2. from google.cloud import bigquery

Code example

>>> from google.cloud import bigquery

Stack trace

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/__init__.py", line 35, in <module>
    from google.cloud.bigquery.client import Client
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/client.py", line 71, in <module>
    from google.cloud.bigquery.dataset import Dataset
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/dataset.py", line 25, in <module>
    from google.cloud.bigquery.routine import RoutineReference
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/routine/__init__.py", line 18, in <module>
    from google.cloud.bigquery.enums import DeterminismLevel
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/enums.py", line 21, in <module>
    from google.cloud.bigquery.query import ScalarQueryParameterType
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/query.py", line 23, in <module>
    from google.cloud.bigquery.table import _parse_schema_resource
  File "/home/scizorman/dev/tmp/foo/.venv/lib/python3.9/site-packages/google/cloud/bigquery/table.py", line 23, in <module>
    import pytz
ModuleNotFoundError: No module named 'pytz'

.venv/lib/python3.9/site-packages/google/cloud/bigquery/table.py

# Copyright 2015 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Define API Tables."""

from __future__ import absolute_import

import copy
import datetime
import functools
import operator
import pytz
...

[hieumdd]

I've found this today.
setup.py no longer has pytz, while table.py still has import pytz

Environment details

• OS type and version: macOS 10.15.6
• Python version: Python 3.8.5
• pip version: pip 20.3.3
• google-cloud-bigquery version: 2.24.0

Steps to reproduce
pipenv install google-cloud-bigquery

• Deploy on GCF with pipenv lock -r > requirements.txt

[EDjur]

Ditto. Also happens on google-cloud-bigquery==2.23.2. Related: googleapis/python-api-core#250

[pietrodn]

I confirm this issue. On my project, this happened:

1. Dependabot attempted to update google-api-core from 1.31.2 to 2.0.0
2. google-api-core==2.0.0 removed the dependency on pytz
3. No other package depended on pytz, so the package was uninstalled
4. google-cloud-bigquery implicitly depends on pytz
5. The tests started failing with this traceback:

   .venv/lib/python3.9/site-packages/google/cloud/bigquery/__init__.py:35: in <module>
       from google.cloud.bigquery.client import Client
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/client.py:71: in <module>
       from google.cloud.bigquery.dataset import Dataset
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/dataset.py:25: in <module>
       from google.cloud.bigquery.routine import RoutineReference
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/routine/__init__.py:18: in <module>
       from google.cloud.bigquery.enums import DeterminismLevel
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/enums.py:21: in <module>
       from google.cloud.bigquery.query import ScalarQueryParameterType
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/query.py:23: in <module>
       from google.cloud.bigquery.table import _parse_schema_resource
   .venv/lib/python3.9/site-packages/google/cloud/bigquery/table.py:23: in <module>
       import pytz
   E   ModuleNotFoundError: No module named 'pytz'
   

However I see that a commit in master removes the implicit dependency of google-cloud-bigquery on pytz.
I guess that the problem will be solved when a new release of the BigQuery lib is cut.

[aciezkowski]

It seems there's a fix for it here #875 planned for 2.24.1, but it has not been released yet -> #879

[plamut]

Right... the new version of api-core dropped the pytz dependency which the python-bigquery library implicitly depends on.

A fix is on the way (15 minutes or so if all goes right).

(and the workaround is to install pytz manually if using an older BigQuery client version)

[plamut]

Released. Sorry folks for the inconvenience!