code: def add_prompt(self, prompt, echo=True):
          
          self.prompts.append((prompt, echo))
docs: Add a prompt to this query.  The prompt should be a (reasonably short)
          string.  Multiple prompts can be added to the same query.
  
          :param str prompt: the user prompt
          :param bool echo:
              ``True`` (default) if the user's response should be echoed;
              ``False`` if not (for a password or similar)