input: Write a function to create an interactive text-based RPG game in Python where the player can move between rooms and battle monsters. The function should include a Player class, a Room class, a Monster class, and a game loop that allows the player to choose actions such as moving and fighting. Ensure that the game loop continues until the player's health drops to zero.
  assert start_game()==True
  assert Player().health == 100
  assert Room().name == ''
  assert Monster().health == 100
  assert Room().add_monster(Monster()) == True
output: def start_game():
      class Player:
          def __init__(self):
              self.health = 100
              self.attack = 10
  
      class Room:
          def __init__(self):
              self.name = ''
              self.monsters = []
  
          def add_monster(self, monster):
              self.monsters.append(monster)
              return True
  
      class Monster:
          def __init__(self):
              self.health = 100
              self.attack = 5
  
      def battle(player, monster):
          while player.health > 0 and monster.health > 0:
              monster.health -= player.attack
              if monster.health <= 0:
                  print("You defeated the monster!")
                  break
              player.health -= monster.attack
              if player.health <= 0:
                  print("You have been defeated by the monster!")
                  break
  
      rooms = [Room() for _ in range(3)]
      rooms[0].name = "Entrance"
      rooms[1].name = "Hallway"
      rooms[2].name = "Chamber"
  
      rooms[1].add_monster(Monster())
      rooms[2].add_monster(Monster())
  
      player = Player()
      current_room = rooms[0]
  
      while player.health > 0:
          print(f"You are in the {current_room.name}.")
          if current_room.monsters:
              print("A monster appears!")
              battle(player, current_room.monsters[0])
              if player.health <= 0:
                  break
              current_room.monsters.pop(0)
          print("Where would you like to go?")
          for i, room in enumerate(rooms):
              if room != current_room:
                  print(f"{i+1}. {room.name}")
          choice = int(input("Enter the number of your choice: ")) - 1
          if 0 <= choice < len(rooms) and rooms[choice] != current_room:
              current_room = rooms[choice]
          else:
              print("Invalid choice. Try again.")
  
      print("Game Over")
      return True