Updated classifier.py

Signed-off-by: Kevin Eykholt <[email protected]>

Author: keykholt

art/estimators/classification/classifier.py

@@ -29,6 +29,7 @@
     LossGradientsMixin,
     DecisionTreeMixin,
 )
+from art.utils import CLASSIFIER_TYPE
 
 
 class InputFilter(ABCMeta):
@@ -117,6 +118,9 @@ def nb_classes(self, nb_classes: int):
 
         self._nb_classes = nb_classes
 
+    def clone_for_refitting(self) -> CLASSIFIER_TYPE:
+        raise NotImplementedError
+
 
 class ClassGradientsMixin(ABC):
     """