def send_streamheader(self, handle, connection):
        response = "HTTP/1.0 200 OK\n" + "Content-Type: text/event-stream\n" + \
            "Access-Control-Allow-Origin: *\r\n" + "\n"

        if connection is not None:
            if not connection.connection_lost:
                connection.send(response)
        elif self.tunnel_client is not None:
                msg = {"cmd": "logresp", "msgid": handle, "header": response, "data": None}
                self.tunnel_client.send(msg)
The preferred way to create a port is to pass a PortSpec with
dataset/ETHPy150Open EricssonResearch/calvin-base/calvin/runtime/north/calvincontrol.py/CalvinControl.send_streamheader--crossover with--dataset/ETHPy150Open VisTrails/VisTrails/vistrails/core/vistrail/port.py/Port.__init__