#!/usr/bin/python3

import asyncio


class MyProtocol(asyncio.DatagramProtocol):
    def connection_made(self, transport):
        self.transport = transport

    async def _datagram_received(self, data, rqaddr):
        print('req from: @%s:%s' % (*rqaddr,))

        loop = asyncio.get_running_loop()
        transport, protocol = await loop.create_datagram_endpoint(asyncio.DatagramProtocol, remote_addr=rqaddr)
        rsaddr = transport.get_extra_info('sockname')
        transport.close()

        print('rsp from: @%s:%s' % (*rsaddr,))

        self.transport.sendto(data, rqaddr)

    def datagram_received(self, data, rqaddr):
        # ISSUE-2
        asyncio.create_task(self._datagram_received(data, rqaddr))


async def main():
    loop = asyncio.get_running_loop()

    transport, protocol = await loop.create_datagram_endpoint(MyProtocol, local_addr=('0.0.0.0', 9999))

    # ISSUE-1
    try:
        await loop.create_future()
    finally:
        transport.close()


if __name__ == '__main__':
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        pass