code: def dl(self, ds_type:DatasetType=DatasetType.Valid)->DeviceDataLoader:
          "Returns appropriate `Dataset` for validation, training, or test (`ds_type`)."
          #TODO: refactor
          return (self.train_dl if ds_type == DatasetType.Train else
                  self.test_dl if ds_type == DatasetType.Test else
                  self.valid_dl if ds_type == DatasetType.Valid else
                  self.single_dl if ds_type == DatasetType.Single else
                  self.fix_dlf dl(self, ds_type:DatasetType=DatasetType.Valid)->DeviceDataLoader:
          "Returns appropriate `Dataset` for validation, training, or test (`ds_type`)."
          #TODO: refactor
          return (self.train_dl if ds_type == DatasetType.Train else
                  self.test_dl if ds_type == DatasetType.Test else
                  self.valid_dl if ds_type == DatasetType.Valid else
                  self.single_dl if ds_type == DatasetType.Single else
                  self.fix_dl)
docs: Returns appropriate `Dataset` for validation, training, or test (`ds_type`).