def is_equal_to_as_set(l1, l2):
    """ return true if two lists contain the same content
    :param l1: first list
    :param l2: second list
    :return: whether lists match
    """
    # Note specifically that set(l1) == set(l2) does not work as expected.
    return len(set(l1).symmetric_difference(set(l2))) == 0