# skfolio.exceptions.DuplicateGroupsError ### *exception* skfolio.exceptions.DuplicateGroupsError Group name appear in multiple group levels. #### add_note(object, /) Exception.add_note(note) – add a note to the exception #### with_traceback(object, /) Exception.with_traceback(tb) – set self._\_traceback_\_ to tb and return self.