'Triggered when the timer from a delayed request fires.
Arguments:
session         -- The request session id
process_fields  -- The fields to request from the devices
flags           -- [optional] flags to pass to the devices, e.g. momentary
Formatted as a dictionary like { "flag name": "flag value" ... }'

def _event_delayed_req(self, session, process_fields, req_flags):

    msg = self.xmpp.Message()
    msg['from'] = self.sessions[session]['to']
    msg['to'] = self.sessions[session]['from']
    msg['started']['seqnr'] = self.sessions[session]['seqnr']
    msg.send()
    if self.threaded:
        tr_req = Thread(target=self._threaded_node_request, args=(session, process_fields, req_flags))
        tr_req.start()
    else:
        self._threaded_node_request(session, process_fields, req_flags)
