TypeError: 'ABCMeta' object is not subscriptable on Python 3.8, google-auth==2.46.0

[timoffex]

Environment details

• OS: macOS
• Python version: 3.8
• pip version: uv-pip 0.6.3 (6d3614eec 2025-02-19)
• google-auth version: 2.46.0

Steps to reproduce

In a fresh Python 3.8 environment, install google-cloud-storage==3.7.0, which pulls in google-auth==2.46.0.

❯ uv venv --python 3.8 .venv-38
❯ source .venv-38/bin/activate
❯ uv pip install google-cloud-storage==3.7.0
Using Python 3.8.20 environment at: .venv-38
Resolved 18 packages in 5ms
Installed 18 packages in 15ms
 + cachetools==5.5.2
 + certifi==2026.1.4
 + charset-normalizer==3.4.4
 + google-api-core==2.28.1
 + google-auth==2.46.0
 + google-cloud-core==2.5.0
 + google-cloud-storage==3.7.0
 + google-crc32c==1.5.0
 + google-resumable-media==2.8.0
 + googleapis-common-protos==1.72.0
 + idna==3.11
 + proto-plus==1.27.0
 + protobuf==5.29.5
 + pyasn1==0.6.1
 + pyasn1-modules==0.4.2
 + requests==2.32.4
 + rsa==4.9.1
 + urllib3==2.2.3

Run import google.cloud.storage in a Python interpreter.

❯ python -c 'import google.cloud.storage'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/Users/timoffex/Documents/workspace/testing/.venv-38/lib/python3.8/site-packages/google/cloud/storage/__init__.py", line 35, in <module>
    from google.cloud.storage.batch import Batch
  File "/Users/timoffex/Documents/workspace/testing/.venv-38/lib/python3.8/site-packages/google/cloud/storage/batch.py", line 42, in <module>
    from google.cloud import _helpers
  File "/Users/timoffex/Documents/workspace/testing/.venv-38/lib/python3.8/site-packages/google/cloud/_helpers/__init__.py", line 30, in <module>
    import google.auth
  File "/Users/timoffex/Documents/workspace/testing/.venv-38/lib/python3.8/site-packages/google/auth/__init__.py", line 22, in <module>
    from google.auth._default import (
  File "/Users/timoffex/Documents/workspace/testing/.venv-38/lib/python3.8/site-packages/google/auth/_default.py", line 598, in <module>
    scopes: Optional[Sequence[str]] = None,
TypeError: 'ABCMeta' object is not subscriptable

[timoffex]

Can even just do python -c 'import google.auth' and avoid installing google-cloud-storage.

[zeno0119]

The root cause seems to be here:

google-auth-library-python/google/auth/_default.py

Line 20 in 5c07e1c

from collections.abc import Sequence

It uses Sequence from collections.abc as a generic type. This syntax is only supported in Python 3.9+ (PEP 585). Since this project supports Python 3.8, we should use from typing import Sequence instead.

[pingleiwandb]

From git history, it is introduced in https://github.com/googleapis/google-auth-library-python/pull/1588/changes

[noobie-bob]

Can this release of https://pypi.org/project/google-auth/2.46.0/ be yanked for python less than v3.9

[daniel-sanche]

This was fixed in #1918, and will be released as 2.47.0

[daniel-sanche]

Ok, v2.47.0 has been released with the fix, thanks everyone!

But just want to give a head's up to everyone impacted by this: Python 3.8 has been EOL for over a year now, and likely won't be supported by new versions of GCP SDKs for too much longer. So it might be a good time to start planning an upgrade