a = 1 b = 2 a, b = b, a # a = 2 , b = 1
def swap0(s1, s2): assert type(s1) == list and type(s2) == list tmp = s1[:] s1[:] = s2 s2[:] = tmp # However, the easier and better way to do a swap in Python is simply: s1, s2 = s2, s1