# next_combo.py

# next_combo.py

def next_combo(values):
    j = [[]]
    for value in values:
        L = len(j)
        j += [i + [value] for i in j]
        for result in j[L:]:
            yield result

values = [1,2,3,4,5,6]

combo = next_combo(values)

while 1:
    try:
        print next(combo)
    except:
        break