code: async def read_line(stream: asyncio.StreamReader) -> bytes:
      
      # Security: this is bounded by the StreamReader's limit (default = 32 KiB).
      line = await stream.readline()
      # Security: this guarantees header values are small (hard-coded = 4 KiB)
      if len(line) > MAX_LINE:
          raise ValueError("Line too long")
      # Not mandatory but safe - https://tools.ietf.org/html/rfc7230#section-3.5
      if not line.endswith(b"\r\n"):
          raise ValueError("Line without CRLF")
      return line[:-2]
docs: Read a single line from ``stream``.
  
      ``stream`` is an :class:`~asyncio.StreamReader`.
  
      Return :class:`bytes` without CRLF.