code: def test_literal_serializable():
      l = literal((add, 1, 2))
      assert pickle.loads(pickle.dumps(l)).data == (add, 1, 2)
  
imports: from __future__ import annotations
  import pickle
  from collections import namedtuple
  import pytest
  from dask.core import flatten, get, get_dependencies, get_deps, getcycle, has_tasks, ishashable, iskey, istask, literal, preorder_traversal, quote, subs, validate_key
  from dask.utils_test import GetFunctionTestMixin, add, inc
label_desc: Use image node_id 25 for calling a global function with example usage: test_literal_serializable() without return types