input: Write a function to generate all permutations of a list of characters using itertools and print each permutation.
  assert permutations(['A', 'B', 'C'])==None
  assert permutations(['X', 'Y'])==None
  assert permutations(['1', '2', '3', '4'])==None
output: def permutations(chars):
      from itertools import permutations
      for p in permutations(chars):
          print(p)