Added _is_neighbors_object() private validation function

Author: sft-managed

imblearn/utils/_validation.py

@@ -66,6 +66,12 @@ def _transfrom_one(self, array, props):
             ret = array
         return ret
 
+def _is_neighbors_object(kneighbors_estimator):
+    neighbors_attributes = [
+        "kneighbors",
+        "kneighbors_graph"
+    ]
+    return all(hasattr(kneighbors_estimator, attr) for attr in neighbors_attributes)
 
 def check_neighbors_object(nn_name, nn_object, additional_neighbor=0):
     """Check the objects is consistent to be a NN.
@@ -93,7 +99,7 @@ def check_neighbors_object(nn_name, nn_object, additional_neighbor=0):
     """
     if isinstance(nn_object, Integral):
         return NearestNeighbors(n_neighbors=nn_object + additional_neighbor)
-    elif hasattr(nn_object, 'kneighbors') and hasattr(nn_object, 'kneighbors_graph'):
+    elif _is_neighbors_object(nn_object):
         return clone(nn_object)
     else:
         raise_isinstance_error(nn_name, [int, KNeighborsMixin], nn_object)