code: def test_getenv_fail(self):
      env = getenv(
          "TEST_ENV_VARIABLE_WHICH_DOES_NOT_EXIST", "hello world"
      )
      self.assertEqual(env, "hello world")
  
file_path: lightly/tests/api/test_utils.py
imports: import os
  import unittest
  from unittest import mock
  import pytest
  from PIL import Image
  from lightly.api.utils import DatasourceType, PIL_to_bytes, get_lightly_server_location_from_env, get_signed_url_destination, getenv, paginate_endpoint, retry
label_desc: Use image node_id 4 for calling the TestUtils obj's underlying member method code with example usage: obj.test_getenv_fail() without return types