input: Write a function to implement an interactive text-based RPG game in Python where the player can move around different rooms and battle monsters. The function should create a Player, multiple Rooms, and Monsters, and then start the game loop where the player can choose to move to a different room or fight a monster in the current room. If the player's health drops to 0 or below, the game should end with a message.
  
  assert start_game()==None
  assert Player().health==100
  assert Room().name==''
  assert Monster().health==100
  assert Player().location=='room one'
  
  # Player class
  class Player(object):
   def __init__(self):
   self.health = 100
   self.location = 'room one'
   self.monsters_killed = 0
  
  # Room class
  class Room(object):
   def __init__(self):
   self.name = ''
   self.description = ''
   self.monsters = []
  
   def add_monster(self, monster):
   self.monsters.append(monster)
  
  # Monster class
  class Monster(object):
   def __init__(self):
   self.name = ''
   self.health = 100
  
   def attack(self, player):
   player.health -= 10
  
  # Function to start the game
  def start_game():
   # Create player, rooms and monsters
   player = Player()
  
  # Main game loop
  while True:
   # Show the current room;
   print(f'You are in {player.location}.')
   # Display available actions
   print('Available actions: move, fight')
   # Get user's action
   response = input('What would you like to do? ').lower()
  
   # Moving to a new room
   if response == 'move':
   # Get the list of available rooms
   # Get the user's destination
   # Move the player to the chosen room
  
  # Fighting a monster
   if response == 'fight':
   # Get all monsters in the current room
   # Get the user's chosen monster
   # Initiate a battle between the player and the monster
  
  # End of the game
   if player.health <= 0:
   print ('You have been defeated!')
   break
  
  if __name__ == '__main__':
   start_game()
output: def start_game():
      # Create player, rooms and monsters
      player = Player()
      room1 = Room()
      room1.name = 'room one'
      room2 = Room()
      room2.name = 'room two'
      monster1 = Monster()
      monster1.name = 'Goblin'
      monster2 = Monster()
      monster2.name = 'Orc'
      room1.add_monster(monster1)
      room2.add_monster(monster2)
  
      rooms = {'room one': room1, 'room two': room2}
  
      # Main game loop
      while True:
          # Show the current room
          print(f'You are in {player.location}.')
          # Display available actions
          print('Available actions: move, fight')
          # Get user's action
          response = input('What would you like to do? ').lower()
  
          # Moving to a new room
          if response == 'move':
              available_rooms = [room for room in rooms if room != player.location]
              print(f'Available rooms: {", ".join(available_rooms)}')
              destination = input('Where would you like to go? ').lower()
              if destination in available_rooms:
                  player.location = destination
              else:
                  print('Invalid room choice.')
  
          # Fighting a monster
          elif response == 'fight':
              current_room = rooms[player.location]
              if current_room.monsters:
                  print(f'Monsters in this room: {", ".join([monster.name for monster in current_room.monsters])}')
                  chosen_monster = input('Which monster would you like to fight? ').lower()
                  monster = next((monster for monster in current_room.monsters if monster.name.lower() == chosen_monster), None)
                  if monster:
                      while player.health > 0 and monster.health > 0:
                          monster.attack(player)
                          if player.health > 0:
                              print(f'You attacked the {monster.name}!')
                              monster.health -= 10
                              if monster.health <= 0:
                                  print(f'You defeated the {monster.name}!')
                                  current_room.monsters.remove(monster)
                                  player.monsters_killed += 1
                          else:
                              print(f'The {monster.name} defeated you!')
                              break
                  else:
                      print('Invalid monster choice.')
              else:
                  print('No monsters in this room.')
  
          # End of the game
          if player.health <= 0:
              print('You have been defeated!')
              break