input: Write a function to implement a decision-making algorithm for a rock-paper-scissors game using Python. The function should take two inputs representing the choices of Player 1 and Player 2 and return the result based on the game rules. If both players make the same choice, the game should return 'It is a draw!'. If Player 1's choice beats Player 2's choice, return 'Player 1 wins!'. If Player 2's choice beats Player 1's choice, return 'Player 2 wins!'.
  
  assert play_game('rock', 'scissors') == 'Player 1 wins!'
  assert play_game('scissors', 'scissors') == 'It is a draw!'
  assert play_game('paper', 'rock') == 'Player 1 wins!'
  assert play_game('scissors', 'paper') == 'Player 1 wins!'
  assert play_game('rock', 'paper') == '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!'