You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.

exchange-calendars-extensions
0.8.4rc21

This version was deleted from PyPI around 2026-01-29. Installing fails with:
$ pip3 install exchange-calendars-extensions==0.8.4rc21 ERROR: Could not find a version that satisfies the requirement exchange-calendars-extensions==0.8.4rc21
View other deleted versions of exchange-calendars-extensions

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/2026-01-28/ \ exchange-calendars-extensions==0.8.4rc21
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Or, download files manually

And install manually via pip:
exchange_calendars_extensions-0.8.4rc21-py3-none-any.whl (29.7KB)
exchange_calendars_extensions-0.8.4rc21.tar.gz (114.5KB)