Revert "bpo-47211: Remove function re.template() and flag re.TEMPLATE (GH-32300)"
This reverts commit b09184bf05.
(cherry picked from commit 16a7e4a0b7)
Co-authored-by: Miro Hrončok <miro@hroncok.cz>
It was initially added to support atomic groups, but that
support was never fully implemented, and CALL was only left
in the compiler, but not interpreter and parser.
ATOMIC_GROUP is now used to support atomic groups.