input: Write a function to implement a decision-making algorithm for a rock-paper-scissors game in Python. The function should take two inputs, `player1` and `player2`, which are the choices made by the two players. The function should return 'Player 1 wins!' if Player 1 wins, 'Player 2 wins!' if Player 2 wins, and 'It is a draw!' if the choices are the same.
  assert play_game('rock', 'scissors') == 'Player 1 wins!'
  assert play_game('paper', 'scissors') == 'Player 2 wins!'
  assert play_game('rock', 'rock') == 'It is a draw!'
  assert play_game('scissors', 'paper') == 'Player 1 wins!'
  assert play_game('paper', 'rock') == 'Player 1 wins!'
  assert play_game('scissors', 'rock') == 'Player 2 wins!'
output: def play_game(player1, player2):
      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!'