import socket
from systemd import daemon, journal

def say(fmt, *args, **kwargs):
    journal.send(('[journal] ' + fmt).format(*args, **kwargs))
    print(fmt.format(*args, **kwargs))

sockets = daemon.listen_fds(True)
say("received sockets {}", sockets)
assert sockets == [3], sockets

s = socket.socket(fileno=daemon.LISTEN_FDS_START)
say("created socket: {} fd={}", s.getsockname(), s.fileno())

s.listen(5)
while True:
    conn, info = s.accept()
    say("received connection {}", info)
    with conn.makefile() as f:
        input = f.read()
        say("connection said {!r}", input)