code: def _get_content_length(self,msg):
          '''从消息中解析Content-length'''
          m = re.search(r'[Cc]ontent-length:\s?(?P<len>\d+)',msg,re.S)
          return (m and int(m.group('len'))) or f _get_content_length(self,msg):
          '''从消息中解析Content-length'''
          m = re.search(r'[Cc]ontent-length:\s?(?P<len>\d+)',msg,re.S)
          return (m and int(m.group('len'))) or 0
docs: 从消息中解析Content-length