def populate(apps, schema_editor):
    LogparserLogrecord = apps.get_model("viewer", "LogparserLogrecord")
    LogparserError = apps.get_model("viewer", "LogparserLogrecord")
    records = LogparserLogrecord.objects.filter(level__in=['ERROR', 'FATAL']).values_list('level', 'message', 'session').distinct()
    d = collections.defaultdict(list)
    for (level,msg,session) in records:
        d[(level,msg)].append(session)

    for (level,msg,sessions) in d.items():
        e = LogparserError(level=level, message=msg)
        e.save()
        e.session.add(*sessions)