Add _upgrade and _add_gens for mpolys#2198
Draft
SoongNoonien wants to merge 6 commits intoNemocas:masterfrom
Draft
Add `_upgrade` and `_add_gens` for mpolys#2198SoongNoonien wants to merge 6 commits intoNemocas:masterfrom
SoongNoonien wants to merge 6 commits intoNemocas:masterfrom