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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def start_user_session(self, username, domain, resource, **kwargs):
 """Method to add a user session for debugging. Accepted parameters are the same as to the constructor of :py:class:`~xmpp_backends.base.UserSession`. """


        kwargs.setdefault('uptime', pytz.utc.localize(datetime.utcnow()))
        kwargs.setdefault('priority', 0)
        kwargs.setdefault('status', 'online')
        kwargs.setdefault('status_text', '')
        kwargs.setdefault('connection_type', CONNECTION_XMPP)
        kwargs.setdefault('encrypted', True)
        kwargs.setdefault('compressed', False)
        kwargs.setdefault('ip_address', '127.0.0.1')
        if six.PY2 and isinstance(kwargs['ip_address'], str):
            # ipaddress constructor does not eat str in py2 :-/
            kwargs['ip_address'] = kwargs['ip_address'].decode('utf-8')
        if isinstance(kwargs['ip_address'], six.string_types):
            kwargs['ip_address'] = ipaddress.ip_address(kwargs['ip_address'])

        user = '%s@%s' % (username, domain)
        session = UserSession(self, username, domain, resource, **kwargs)

        data = self.module.get(user)
        if data is None:
            raise UserNotFound(username, domain, resource)

        data.setdefault('sessions', set())
        if isinstance(data['sessions'], list):
            # Cast old data to set
            data['sessions'] = set(data['sessions'])

        data['sessions'].add(session)
        self.module.set(user, data)

        all_sessions = self.module.get('all_sessions', set())
        all_sessions.add(session)
        self.module.set('all_sessions', all_sessions)