typo

pandas/core/groupby/generic.py

@@ -590,7 +590,7 @@ def transform(self, func, *args, **kwargs):
 
         obj = self._obj_with_exclusions
 
-        # nuiscance columns
+        # nuisance columns
         if not result.columns.equals(obj.columns):
             return self._transform_general(func, *args, **kwargs)