Registering a service in a thread about mdns HOT 12 CLOSED

 python3 ex.py 
Traceback (most recent call last):
  File "ex.py", line 31, in <module>
    info = ServiceInfo(d, n, inet_aton('127.0.0.1'), 12345, properties=txt)
  File "/home/titilambert/projets_opensource/mdns/mdns/zeroconf.py", line 1367, in __init__
    self.set_properties(self.properties)
  File "/home/titilambert/projets_opensource/mdns/mdns/zeroconf.py", line 1393, in set_properties
    self.sync_properties()
  File "/home/titilambert/projets_opensource/mdns/mdns/zeroconf.py", line 1387, in sync_properties
    self.text = dict_to_text(self.properties)
  File "/home/titilambert/projets_opensource/mdns/mdns/zeroconf.py", line 237, in dict_to_text
    result = ''.join((result, struct.pack('!c', chr(len(item))), item))
struct.error: char format requires a bytes object of length 1

import sys
from mdns.zeroconf import *
from socket import *

n = 'bala3._presence._tcp.local.'
d = '_presence._tcp.local.'

txt = {}
txt['1st'] = "self.fullname3"
txt['last'] = ""
txt['status'] = 'avail'
txt['port.p2pj'] = 12345
txt['nick'] = "self.fullnick3"
#txt['node'] = self.node
txt['jid'] = "self.node"
txt['email'] = "self.node"
txt['version'] = 1
txt['txtvers'] = 1
records = [16]
info = ServiceInfo(d, n, inet_aton('127.0.0.1'), 12345, properties=txt)
r.register_service(info)
r.engine.join()