Sam's all permutations of a list in python

node_permutations_python.py

# Sam's python implementation
def permutations(listt): # apparently 'list' is a reserved keyword in python (or at least is a different color in the editor)
    if len(listt) == 1:
        yield listt
        return
    else:
        for i, o in enumerate(listt):
            listt_copy = listt.copy()
            del listt_copy[i]
            for perm in permutations(listt_copy):
                yield [o] + perm # still not quite clear on how the yield statements work here