code: def test_fit(mock_args):
      """
      test the fit model functionality
      """
      assert mock_args is not None
      Igel(**mock_args.fit)
      assert Constants.model_results_dir.exists() == True
      assert Constants.description_file.exists() == True
      assert Constants.evaluation_file.exists() == False
  
file_path: igel/tests/test_igel/test_igel.py
imports: import os
  import pytest
  from igel import Igel
  from .constants import Constants
  from .helper import remove_folder
  from .mock import MockCliArgs
label_desc: Use image node_id 2 for calling a global function with example usage: test_fit(mock_args) without return types