code: def load_tests(loader, tests, pattern):
      tests.addTest(doctest.DocTestSuite())
      return tests
  
file_path: cpython/Lib/test/test_getopt.py
imports: from test.support.os_helper import EnvironmentVarGuard
  import doctest
  import unittest
  import getopt
label_desc: Use image node_id 2 for calling a global function with example usage: load_tests(loader, tests, pattern) and returns: tests