import socket

s = socket.socket()
host = socket.gethostname()
port = 22445
s.bind((host, port))
s.listen()


while True:
    (connection, addr) = s.accept()
    print('verbindung von ', addr)
    bytes = connection.recv(1024)
    msg = bytes.decode('utf-8')
    msg = msg.upper()
    connection.send(msg.encode('utf-8'))
    connection.close()