code: def sanitized_uri(self):
          
          if self._sanitized_uri is None:
              _parsed = copy.copy(self._parsed_uri)
              if 'username' in _parsed:
                  _parsed['password'] = 'secret'
              _parsed['nodelist'] = [_parsed['nodelist'][0]]
              self._sanitized_uri = _format_mongodb_uri(_parsed)
          return self._sanitized_uri
docs: Return the database URI we're using in a format sensible for logging etc.
  
          :return: db_uri