BUG: Index with duplicate labels raises ValueError in Dataframe.query

pandas/core/frame.py

@@ -9,6 +9,7 @@
 labeling information
 """
 from __future__ import annotations
+from pandas.core.indexes.range import RangeIndex
 
 import collections
 from collections import abc
@@ -4339,6 +4340,24 @@ def query(self, expr: str, *, inplace: Literal[False] = ..., **kwargs) -> DataFr
     def query(self, expr: str, *, inplace: Literal[True], **kwargs) -> None:
         ...
 
+    def query_with_duplicate_index(self, expr, engine='numexpr'):
+
+        # Create a copy of the dataframe with a unique index to avoid reindexing errors
+        unique_index = RangeIndex(len(self.index))
+        df_copy = self.copy()
+        df_copy.index = unique_index
+
+        # Filter the copied dataframe
+        filtered_df = df_copy.query(expr, engine=engine)
+
+        # Map the filtered index back to the original index labels
+        index_mapping = dict(zip(unique_index, self.index))
+        filtered_df.index = filtered_df.index.map(index_mapping)
+
+        # Return the filtered dataframe
+        return filtered_df
+
+
     @overload
     def query(self, expr: str, *, inplace: bool = ..., **kwargs) -> DataFrame | None:
         ...