code: def testImportFuncFromSource(self):
      source_data_dir = os.path.join(
          os.path.dirname(__file__), "testdata"
      )
      test_fn_file = os.path.join(source_data_dir, "test_fn.ext")
      fn_1 = import_utils.import_func_from_source(
          test_fn_file, "test_fn"
      )
      fn_2 = import_utils.import_func_from_source(
          test_fn_file, "test_fn"
      )
      self.assertEqual(10, fn_1([1, 2, 3, 4]))
      self.assertEqual(10, fn_2([1, 2, 3, 4]))
  
file_path: tfx/tfx/utils/import_utils_test.py
imports: import importlib
  import os
  import sys
  import tensorflow
  from tfx.utils import import_utils
  from tfx.utils.testdata import test_fn
label_desc: Use image node_id 2 for calling the ImportUtilsTest obj's underlying member method code with example usage: obj.testImportFuncFromSource() without return types