'Returns True if \'self\' is a proper superset of \'other\'.
Examples
>>> from sympy import Interval
>>> Interval(0, 1).is_proper_superset(Interval(0, 0.5))
True
>>> Interval(0, 1).is_proper_superset(Interval(0, 1))
False'

def is_proper_superset(self, other):

    if isinstance(other, Set):
        return ((self != other) and self.is_superset(other))
    else:
        raise ValueError(("Unknown    argument    '%s'" % other))
