code: def _agent_import_failed(trace):
      
  
      class _AgentImportFailed(Trainer):
          _name = "AgentImportFailed"
          _default_config = with_common_config({})
  
          def _setup(self, config):
              raise ImportError(trace)
  
      return _AgentImportFailed
docs: Returns dummy agent class for if PyTorch etc. is not installed.