code: def create_session(self):
          
          req_url = '%s/%s' % (self.__webfsapi, 'CREATE_SESSION')
          sid = yield from self.__session.get(req_url, params=dict(pin=self.pin),
                                              timeout = self.timeout)
          text = yield from sid.text(encoding='utf-8')
          doc = objectify.fromstring(text)
          return doc.sessionId.text
docs: Create a session on the frontier silicon device.