code: def strip_prompt(self, a_string):
          
          response_list = a_string.split(self.RESPONSE_RETURN)
          last_line = response_list[-1]
          if self.base_prompt in last_line:
              return self.RESPONSE_RETURN.join(response_list[:-1])
          else:
              return a_string
docs: Strip the trailing router prompt from the output.
  
          :param a_string: Returned string from device
          :type a_string: str