def is_variant(record):
    """
    Return true if record is a variant
    Standard pyvcf `.is_snp` does not work correctly for
    GATK's GVCF format
    :param record: pyvcf record
    :return:
    """
    alts = set(list(map(str, record.ALT)))
    non_variant_alts = {".", "<NON_REF>"}
    true_alts = alts - non_variant_alts
    return len(true_alts) >= 1