code: def session_exists(self, ticket):
          '''
          Test if a session records exists for a service ticket.
          '''
          assert isinstance(self.session_storage_adapter, CASSessionAdapter)
          exists = self.session_storage_adapter.exists(ticket)
          logging.debug('[CAS] Session [{}] exists: {}'.format(ticket, exists))
          return existf session_exists(self, ticket):
          '''
          Test if a session records exists for a service ticket.
          '''
          assert isinstance(self.session_storage_adapter, CASSessionAdapter)
          exists = self.session_storage_adapter.exists(ticket)
          logging.debug('[CAS] Session [{}] exists: {}'.format(ticket, exists))
          return exists
docs: Test if a session records exists for a service ticket.