gistfile1.py

def all_subsets(*elements):
    # ensure elements is indexable and contains only unique values
    elements = list(set(elements))
    
    # Each bit pattern in an n-bit bitfield corresponds to a unique subset
    # of an n-element set. Iterate over all such bitfields where
    # n = len(elements).
    for permutation_bits in xrange(2**len(elements)):
        indexes = [
            i
            for i in xrange(len(elements))
            if (1 << i) & permutation_bits != 0
        ]
        yield set(elements[i] for i in indexes)