def validate_unique_contests():
    # Get all election ids
    election_ids = list(Contest.objects.distinct('election_id'))
    for elec_id in election_ids:
        contests = Contest.objects.filter(election_id=elec_id)
        # compare the number of contest records to unique set of contests for that election
        count = contests.count()
        expected = len(list(contests.distinct('slug')))
        try:
            assert expected == count
        except AssertionError:
            raise AssertionError("%s contests expected for elec_id '%s', but %s found" % (expected, elec_id, count))
    print "PASS: unique contests counts found for all elections"
Should have a unique set of contests for all elections
dataset/ETHPy150Open openelections/openelections-core/openelex/us/md/validate/__init__.py/validate_unique_contests