from twisted.internet import reactor, protocol
# a client protocol
class EchoClient(protocol.Protocol):
    """Once connected, send a message, then print the result."""
    def connectionMade(self):
        self.transport.write(b"hello, world!")
    def dataReceived(self, data):
        "As soon as any data is received, write it back."
        print("Server said:", data)
        self.transport.loseConnection()
    def connectionLost(self, reason):
        print("connection lost")
class EchoFactory(protocol.ClientFactory):
    protocol = EchoClient
    def clientConnectionFailed(self, connector, reason):
        print("Connection failed - goodbye!")
        reactor.stop()
    def clientConnectionLost(self, connector, reason):
        print("Connection lost - goodbye!")
        reactor.stop()
# this connects the protocol to a server running on port 8000
def main():
    f = EchoFactory()
    reactor.connectTCP("localhost", 1234, f)
    reactor.run()
# this only runs if the module was *not* imported
if __name__ == '__main__':
    main()

 from socket import socket; from threading import Thread
stop = False
sock = socket()
sock.bind(('localhost', 1234))
sock.listen()
sockets = []
def accepting():
    while not stop:
        u, ip = sock.accept()
        u.setblocking(False)
        sockets.append((u, ip))
def receiving():
    while not  stop:
        socks = sockets[:]  # Если массив изменит размер во время итерации будет ошибка, а потока два
        for sock_ in socks:
            try:
                data = sock_[0].recv(10000)  # Измени размер если известен фиксированый размер пакетов
                _ = 1 / bool(data)
            except OSError: continue  # ничего нет
            except ZeroDivisionError:  # сокет отрубился
                sockets.pop(sockets.index(sock_))
                sock_[0].close()
                continue
            try:
                print(data.decode())
            except UnicodeDecodeError:
                print('data decoding failure') # дата не текст
thrd1, thrd2 = Thread(target=accepting), Thread(target=receiving)
thrd1.start()
thrd2.start()
while True:
    if input("Type STOP to stop server: ") == "STOP":
        stop = True
        for sock_ in sockets:
            sock_[0].close()
        break