input: from typing import Tuple, Literal
  
  
  def play_game(player1: Literal['rock', 'paper', 'scissors'],
                player2: Literal['rock', 'paper', 'scissors']) -> str:
      """ Implements the rule of rock, paper, scissors game and decides the winner.
      Returns a string indicating the result.
      >>> play_game('rock', 'scissors')
      'Player 1 wins!'
      >>> play_game('scissors', 'scissors')
      'It is a draw!'
      >>> play_game('paper', 'rock') 
      'Player 1 wins!'
      """
output:     if player1 == player2:
          return 'It is a draw!'
      elif (player1 == 'rock' and player2 == 'scissors') or \
           (player1 == 'scissors' and player2 == 'paper') or \
           (player1 == 'paper' and player2 == 'rock'):
          return 'Player 1 wins!'
      else:
          return 'Player 2 wins!'