This directory should contain only installed packages.
It is recommend to use wheel files for that purpose instead of ./setup.py
or pip because it leads to cleaner installations. Glyco has been designed with that. It is a simple interface to pip to generate and install wheel files locally, without interacting with pypi.
More information can be found here: https://chromium.googlesource.com/infra/infra.git/+/master/glyco/README.md