import re


def does_not_have_bad_pairs(chars):
    """
    It does not contain the strings ab, cd, pq, or xy, even if they are part of
    one of the other requirements.
    """
    bad_pairs = ['ab', 'cd', 'pq', 'xy']
    if not re.search('|'.join(bad_pairs), chars):
        return True
    return False