def list_diff(li1, li2):
    """Returns the subset of lists that are present in li1 but absent in li2.

        Args:
            li1: The first list (a superset of li2).
            li2: The second list (a subset of li1)

        Returns:
            list: a list of the elements present in li1, but not li2."""
    return (list(list(set(li1)-set(li2)) + list(set(li2)-set(li1))))