code: def _create_connection(self):
          
          db = psycopg2.connect(database=self.dbname,
                                  user=self.user, password=self.password,
                                  host=self.host, port=self.port)
          if 'psycopg2.extras' in sys.modules:
              psycopg2.extras.register_hstore(db)
          return db
docs: .. :py:method::
  
                If we hava several hosts, we can random choice one to connect