python permute array
# A Python program to print all permutations using library function
from itertools import permutations
perm = permutations([1, 2, 3])
for i in list(perm):
print (i)
# (1, 2, 3)
# (1, 3, 2)
# (2, 1, 3)
# (2, 3, 1)
# (3, 1, 2)
# (3, 2, 1)