code: def open(cls, sock, chunk_type, isatty, chunk_eof_type=None, buf_size=None, select_timeout=None):
      
      with cls.open_multi(sock,
                          (chunk_type,),
                          (isatty,),
                          chunk_eof_type,
                          buf_size,
                          select_timeout) as ctx:
        yield ctx
docs: Yields the write side of a pipe that will copy appropriately chunked values to a socket.