def METHOD_NAME(self, trainer, pl_module) -> None:
    # create sparsifier
    self.data_sparsifier = self.data_sparsifier_class(**self.data_sparsifier_args)
    self.sparsified = deepcopy(pl_module.model)
    _attach_model_to_data_sparsifier(self.sparsified, self.data_sparsifier)  # just to populate the base_sl in the scheduler
    # create scheduler
    args = deepcopy(self.data_scheduler_args)
    args['data_sparsifier'] = self.data_sparsifier
    self.data_scheduler = self.data_scheduler_class(**args)