add slice_rows to interchange protocol

Author: MarcoGorelli

protocol/dataframe_protocol.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from abc import (
     ABC,
     abstractmethod,
@@ -476,6 +478,31 @@ def select_columns_by_name(self, names: Sequence[str]) -> "DataFrame":
         """
         pass
 
+    @abstractmethod
+    def slice_rows(
+        self,
+        start: int | None = None,
+        stop: int | None = None,
+        step: int | None = None,
+    ) -> DataFrame:
+        """
+        Select a subset of rows corresponding to a slice.
+
+        Parameters
+        ----------
+        start : int or None
+            If None, starts at 0.
+        stop : int or None
+            If None, stops at the end.
+        step : int or None
+            If None, uses the default step of 1.
+
+        Returns
+        -------
+        DataFrame
+        """
+        pass
+
     @abstractmethod
     def get_chunks(self, n_chunks: Optional[int] = None) -> Iterable["DataFrame"]:
         """