text: import os
  
  import pandas as pd
  import pytest
  
  from sklearn.linear_model import LinearRegression
  
  from litreading.utils.cli import Instanciator
  from litreading.utils.files import open_file
  
  
  def test_utils_open_file():
      dir_path = os.path.dirname(os.path.abspath(__file__))
      test_path = "/samples/test_data.csv"
      df = open_file(dir_path + test_path, sep=",")
      df_test = pd.read_csv(dir_path + test_path)
      assert df.equals(df_test)
  
  
  def test_instanciator_init():
      available_objects = dict(default=LinearRegression)
      Instanciator(available_objects, "test object")
  
  
  @pytest.mark.parametrize("parameters", [None, {}, {"normalize": True}])
  def test_instanciator_instanciate(parameters):
      available_objects = dict(default=LinearRegression)
      Instanciator(available_objects, "test object").instanciate("default", parameters)
  
  
  def test_instanciator_instanciate_error():
      available_objects = dict(default=LinearRegression)
      i = Instanciator(available_objects, "test object")
      with pytest.raises(ValueError):
          i.instanciate("key_not_in_dict")
  