call finalize in DataFrame.duplicated

Author: arw2019

pandas/core/frame.py

@@ -5285,7 +5285,8 @@ def f(vals):
         labels, shape = map(list, zip(*map(f, vals)))
 
         ids = get_group_index(labels, shape, sort=False, xnull=False)
-        return self._constructor_sliced(duplicated_int64(ids, keep), index=self.index)
+        result = self._constructor_sliced(duplicated_int64(ids, keep), index=self.index)
+        return result.__finalize__(self, method="duplicated")
 
     # ----------------------------------------------------------------------
     # Sorting

pandas/tests/generic/test_finalize.py

@@ -115,10 +115,7 @@
     (pd.DataFrame, frame_data, operator.methodcaller("notnull")),
     (pd.DataFrame, frame_data, operator.methodcaller("dropna")),
     (pd.DataFrame, frame_data, operator.methodcaller("drop_duplicates")),
-    pytest.param(
-        (pd.DataFrame, frame_data, operator.methodcaller("duplicated")),
-        marks=not_implemented_mark,
-    ),
+    (pd.DataFrame, frame_data, operator.methodcaller("duplicated")),
     (pd.DataFrame, frame_data, operator.methodcaller("sort_values", by="A")),
     (pd.DataFrame, frame_data, operator.methodcaller("sort_index")),
     (pd.DataFrame, frame_data, operator.methodcaller("nlargest", 1, "A")),