text: from pymongo import MongoClient
  
  
  class MongoService(object):
      _instance = None
      _client = None
      _db = None
  
      @classmethod
      def get_instance(cls, *args, **kwargs):
          if cls._instance is None:
              cls._instance = super().__new__(cls, *args, **kwargs)
              cls.__init__(cls._instance)
          return cls._instance
  
      def __init__(self):
          self._client = MongoClient("localhost", 27017)
          self._db = self._client.db
  