• I have searched the issues of this repo and believe that this is not a duplicate.
• I have searched the documentation and believe that my question is not covered.

Feature Request

Adding support for --system-site-packages, as described in venv documentation, makes possible to have a set of base common packages available for a number of virtual environments, thus saving disk space and reducing environment creation time. I believe that this option gives some useful extra flexibility on package and environment management.