Perform PUT /rooms/$room_id/send/$event_type

        Args:
            room_id (str): The room ID to send the message event in.
            event_type (str): The event type to send.
            content (dict): The JSON content to send.
            txn_id (int): Optional. The transaction ID to use.
            timestamp (int): Set origin_server_ts (For application services only)

def send_message_event(self, room_id, event_type, content, txn_id=None,
                           timestamp=None):
        """Perform PUT /rooms/$room_id/send/$event_type

        Args:
            room_id (str): The room ID to send the message event in.
            event_type (str): The event type to send.
            content (dict): The JSON content to send.
            txn_id (int): Optional. The transaction ID to use.
            timestamp (int): Set origin_server_ts (For application services only)
        """
        if not txn_id:
            txn_id = self._make_txn_id()

        path = "/rooms/%s/send/%s/%s" % (
            quote(room_id), quote(event_type), quote(str(txn_id)),
        )
        params = {}
        if timestamp:
            params["ts"] = timestamp
        return self._send("PUT", path, content, query_params=params)