You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
python-cos-sdk-v5 was reported malicious
OSV:MAL-2023-8368 - Malicious code in python-cos-sdk-v5 (PyPI)

python-cos-sdk-v5
1.9.25

This version was deleted from PyPI around 2023-09-29. Installing fails with:
$ pip3 install python-cos-sdk-v5==1.9.25 ERROR: Could not find a version that satisfies the requirement python-cos-sdk-v5==1.9.25
View other deleted versions of python-cos-sdk-v5

Install through StableBuild

You can install this package from StableBuild's PyPI snapshots from before the version was deleted:
pip3 install \ -i https://YOUR_API_KEY.pypimirror.stablebuild.com/2023-09-28/ \ python-cos-sdk-v5==1.9.25
Sign up for StableBuild to get an API key (it's free and takes <60 seconds!)

Or, download files manually

And install manually via pip:
python-cos-sdk-v5-1.9.25.tar.gz (93.8KB)