input: Write a python function to check if two words are valid sudoku pairs.
  assert is_sudoku_valid_pair("ready", "steady") == False
  assert is_sudoku_valid_pair("apple", "orange") == False
  assert is_sudoku_valid_pair("cat", "dog") == True
output: def is_sudoku_valid_pair(word1, word2):
      if len(word1) != len(word2):
          return False
      return len(set(word1) & set(word2)) == 0