You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
ensmallen was reported malicious
OSV:MAL-2026-5315 - Malicious code in ensmallen (PyPI)

ensmallen
0.8.27

This version was deleted from PyPI around 2026-06-08. Installing fails with:
$ pip3 install ensmallen==0.8.27 ERROR: Could not find a version that satisfies the requirement ensmallen==0.8.27
View other deleted versions of ensmallen

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/2026-06-07/ \ ensmallen==0.8.27
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Or, download files manually

And install manually via pip:
ensmallen-0.8.27-cp37-abi3-macosx_10_7_x86_64.whl (18.2MB)
ensmallen-0.8.27-cp37-abi3-manylinux_2_12_x86_64.manylinux2010_x86_64.whl (19.0MB)
ensmallen-0.8.27-cp37-abi3-win_amd64.whl (19.1MB)