code: def unittests():
      """
      Short tests.
  
      Runs on CircleCI on every commit. Returns everything in the tests root directory.
      """
      test_loader = unittest.TestLoader()
      test_suite = test_loader.discover("test", pattern="*_test.py")
      test_suite = _circleci_parallelism(test_suite)
      return test_suite
  
imports: import os
  import random
  import unittest
  from itertools import chain
label_desc: Use image node_id 2 for calling a global function with example usage: unittests() and returns: test_suite