docs: def read_and_write(self, reader, writer, chunk_size):
          """
          Read ``chunk_size`` from ``reader``, writing result to ``writer``.
  
          Returns ``None`` if successful, or ``True`` if the read was empty.
  
          .. versionadded:: 2.0
          """
          data = reader.recv(chunk_size)
          if len(data) == 0:
              return True
          writer.sendall(data)