docs: def normalize_linefeeds(self, a_string):
          """Convert `\r\r\n`,`\r\n`, `\n\r` to `\n.`
  
          :param a_string: A string that may have non-normalized line feeds
              i.e. output returned from device, or a device prompt
          :type a_string: str
          """
          newline = re.compile("(\r\r\r\n|\r\r\n|\r\n|\n\r)")
          a_string = newline.sub(self.RESPONSE_RETURN, a_string)
          if self.RESPONSE_RETURN == "\n":
              # Convert any remaining \r to \n
              return re.sub("\r", self.RESPONSE_RETURN, a_string)