code: def save_model(self, model_name: str = "catboost"):
      save_path = os.path.join(
          default_fedot_data_dir(), f"catboost/{model_name}.cbm"
      )
      self.model.save_model(save_path, format="cbm")
  
imports: import os
  from typing import Optional
  import numpy
  import pandas
  from catboost import CatBoostClassifier, CatBoostRegressor, Pool
  from matplotlib import pyplot
  from fedot.core.data.data import InputData
  from fedot.core.data.data_split import train_test_data_setup
  from fedot.core.operations.evaluation.operation_implementations.implementation_interfaces import ModelImplementation
  from fedot.core.operations.operation_parameters import OperationParameters
  from fedot.core.utils import default_fedot_data_dir
label_desc: Use image node_id 6 for calling the FedotCatBoostImplementation obj's underlying member method code with example usage: obj.save_model(model_name) without return types