code: def send(self, event):
          
          data_list = self.send_with_data_passthrough(event)
          if data_list is None:
              return None
          else:
              return b"".join(data_list)
docs: Convert a high-level event into bytes that can be sent to the peer,
          while updating our internal state machine.
  
          Args:
              event: The :ref:`event <events>` to send.
  
          Returns:
              If ``type(event) is ConnectionClosed``, then returns
              ``None``. Otherwise, returns a :term:`bytes-like object`.
  
          Raises:
              LocalProtocolError:
                  Sending this event at this time would violate our
                  understanding of the HTTP/1.1 protocol.
  
          If this method raises any exception then it also sets
          :attr:`Connection.our_state` to :data:`ERROR` -- see
          :ref:`error-handling` for discussion.