--- a/twisted/plugins/pubsub.py	Fri Aug 16 12:48:34 2019 +0200
+++ b/twisted/plugins/pubsub.py	Fri Aug 16 12:53:33 2019 +0200
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 #-*- coding: utf-8 -*-
 
 # Copyright (c) 2012-2019 Jérôme Poisson
@@ -67,7 +67,7 @@
 from wokkel import pubsub
 from wokkel import rsm
 from wokkel import mam
-from zope.interface import implements
+from zope.interface import implementer
 
 from sat_pubsub import const
 from sat_pubsub import mam as pubsub_mam
@@ -77,19 +77,19 @@
 from sat_pubsub.privilege import PrivilegesHandler
 from sat_pubsub.delegation import DelegationsHandler
 from os.path import expanduser, realpath
-import ConfigParser
+import configparser
 
 
 def coerceListType(value):
-    return csv.reader(
+    return next(csv.reader(
         [value], delimiter=",", quotechar='"', skipinitialspace=True
-    ).next()
+    ))
 
 
 def coerceJidListType(value):
     values = [JID(v) for v in coerceListType(value)]
     if any((j.resource for j in values)):
-        raise ValueError(u"you must use bare jids")
+        raise ValueError("you must use bare jids")
     return values
 
 
@@ -112,7 +112,7 @@
      coerceJidListType]
     ]
 
-CONFIG_FILENAME = u'sat'
+CONFIG_FILENAME = 'sat'
 # List of the configuration filenames sorted by ascending priority
 CONFIG_FILES = [realpath(expanduser(path) + CONFIG_FILENAME + '.conf') for path in (
     '/etc/', '/etc/{}/'.format(CONFIG_FILENAME),
@@ -142,23 +142,21 @@
         # if the  options values are the hard-coded ones or if they have been passed on the command line.
 
         # FIXME: must be refactored + code can be factorised with backend
-        config_parser = ConfigParser.SafeConfigParser()
+        config_parser = configparser.ConfigParser()
         config_parser.read(CONFIG_FILES)
         for param in self.optParameters + OPT_PARAMETERS_CFG:
             name = param[0]
             try:
                 value = config_parser.get(CONFIG_SECTION, name)
-                if isinstance(value, unicode):
-                    value = value.encode('utf-8')
                 try:
                     param[2] = param[4](value)
                 except IndexError: # the coerce method is optional
                     param[2] = value
                 except Exception as e:
-                    log.err(u'Invalid value for setting "{name}": {msg}'.format(
+                    log.err('Invalid value for setting "{name}": {msg}'.format(
                         name=name, msg=e))
                     sys.exit(1)
-            except (ConfigParser.NoSectionError, ConfigParser.NoOptionError):
+            except (configparser.NoSectionError, configparser.NoOptionError):
                 pass
         usage.Options.__init__(self)
         for opt_data in OPT_PARAMETERS_CFG:
@@ -173,10 +171,10 @@
         self['jid'] = JID(self['jid']) if self['jid'] else None
 
 
+@implementer(IServiceMaker, IPlugin)
 class SatPubsubMaker(object):
-    implements(IServiceMaker, IPlugin)
     tapname = "sat-pubsub"
-    description = u"Salut à Toi Publish-Subscribe Service Component".encode('utf-8')
+    description = "Salut à Toi Publish-Subscribe Service Component"
     options = Options
 
     def makeService(self, config):
@@ -198,7 +196,7 @@
                 'db_port': 'port',
             }
             kwargs = {}
-            for config_k, k in keys_map.iteritems():
+            for config_k, k in keys_map.items():
                 v = config.get(config_k)
                 if v is None:
                     continue
@@ -230,7 +228,7 @@
             cs.logTraffic = True
 
         FallbackHandler().setHandlerParent(cs)
-        VersionHandler(u'SàT Pubsub', sat_pubsub.__version__).setHandlerParent(cs)
+        VersionHandler('SàT Pubsub', sat_pubsub.__version__).setHandlerParent(cs)
         DiscoHandler().setHandlerParent(cs)
 
         ph = PrivilegesHandler(config['jid'])