code: def test_sum_receives_few_values():
      component = Sum()
      assert component.run(values=[10, 2]) == {"total": 12}
  
imports: from haystack.testing.sample_components import Sum
  from haystack.core.serialization import component_to_dict, component_from_dict
label_desc: Use image node_id 3 for calling a global function with example usage: test_sum_receives_few_values() without return types