diff --git a/lib/mpl_toolkits/axes_grid1/inset_locator.py b/lib/mpl_toolkits/axes_grid1/inset_locator.py
index 98f1402ec09f..e2d403e8aecf 100644
--- a/lib/mpl_toolkits/axes_grid1/inset_locator.py
+++ b/lib/mpl_toolkits/axes_grid1/inset_locator.py
@@ -578,7 +578,7 @@ def mark_inset(parent_axes, inset_axes, loc1, loc2, **kwargs):
         The patches connecting two corners of the inset axes and its area.
     """
     rect = TransformedBbox(inset_axes.viewLim, parent_axes.transData)
-    
+
     fill = kwargs.pop("fill", False)
     pp = BboxPatch(rect, fill=fill, **kwargs)
     parent_axes.add_patch(pp)