added TODO

Author: nabenabe0928

autoPyTorch/datasets/resampling_strategy.py

@@ -64,6 +64,7 @@ def is_stratified(self) -> bool:
 
 
 class HoldoutValTypes(IntEnum):
+    """TODO: change to enum using functools.partial"""
     """The type of hold out validation (refer to CrossValTypes' doc-string)"""
     holdout_validation = 6
     stratified_holdout_validation = 7