fix migration from pre-3.13.1 versions (closes #2846978)
Need to check the existence of the asource column before the first call
to eid_type_source.
# -*- 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"""