code: def set_base_prompt(
          self, pri_prompt_terminator=">", alt_prompt_terminator="]", delay_factor=1
      ):
          
          log.debug("In set_base_prompt")
          delay_factor = self.select_delay_factor(delay_factor)
          self.clear_buffer()
          self.write_channel(self.RETURN)
          time.sleep(0.5 * delay_factor)
  
          prompt = self.read_channel()
          prompt = self.normalize_linefeeds(prompt)
  
          # If multiple lines in the output take the last line
          prompt = prompt.split(self.RESPONSE_RETURN)[-1]
          prompt = prompt.strip()
  
          # Check that ends with a valid terminator character
          if not prompt[-1] in (pri_prompt_terminator, alt_prompt_terminator):
              raise ValueError("Router prompt not found: {0}".format(prompt))
  
          # Strip off any leading HRP_. characters for USGv5 HA
          prompt = re.sub(r"^HRP_.", "", prompt, flags=re.M)
  
          # Strip off leading and trailing terminator
          prompt = prompt[1:-1]
          prompt = prompt.strip()
          self.base_prompt = prompt
          log.debug("prompt: {0}".format(self.base_prompt))
  
          return self.base_prompt
docs: Sets self.base_prompt
  
          Used as delimiter for stripping of trailing prompt in output.
  
          Should be set to something that is general and applies in multiple contexts. For Comware
          this will be the router prompt with < > or [ ] stripped off.
  
          This will be set on logging in, but not when entering system-view