input: Write a function to check if two sequences are equal regardless of the order of elements.
  assert is_equal([1, 2, 3], [3, 2, 1])==True
  assert is_equal(['a', 'b', 'c'], ['c', 'a', 'b'])==True
  assert is_equal([1, 2, 3], [4, 5, 6])==False
output: def is_equal(seq1, seq2):
      return sorted(seq1) == sorted(seq2)