def fzs(*args):
    """
    Generate a set of frozensets of args. This is needed, because set cannot be a member of a set.

    >>> fzs({'a', 'b'}, 'c') == {frozenset({'a', 'b'}), frozenset({'c'})}
    """
    return {frozenset(s) if isinstance(s, set) else frozenset({s}) for s in args}