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

fbgemm-gpu-cpu
0.7.0rc0

This version was deleted from PyPI around 2024-04-25. Installing fails with:
$ pip3 install fbgemm-gpu-cpu==0.7.0rc0 ERROR: Could not find a version that satisfies the requirement fbgemm-gpu-cpu==0.7.0rc0