DOC: Add return value for Index.slice_locs when label not found #32680

pandas/core/indexes/base.py

@@ -6447,6 +6447,8 @@ def slice_locs(self, start=None, end=None, step=None) -> tuple[int, int]:
         Notes
         -----
         This method only works if the index is monotonic or unique.
+        If a non-existent label is provided the return slice location will be
+        where the label would be inserted to maintain the monotonic property.
 
         Examples
         --------