[migration/3.21] idempotency fixes
Drop constraints before (re)creating them
This is postgresql-specific syntax, sqlserver needs work.
# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s specific hooks and operations"""