code: def test_pipeline(tmp_path):
      pipeline = Pipeline()
      pipeline.add_component("with_defaults", WithDefault())
      pipeline.draw(tmp_path / "default_value.png")
  
      # Pass all the inputs
      results = pipeline.run({"with_defaults": {"a": 40, "b": 30}})
      assert results == {"with_defaults": {"c": 70}}
  
      # Rely on default value for 'b'
      results = pipeline.run({"with_defaults": {"a": 40}})
      assert results == {"with_defaults": {"c": 42}}
  
imports: from pathlib import Path
  from haystack.core.component import component
  from haystack.core.pipeline import Pipeline
  import logging
label_desc: Use image node_id 1 for calling a global function with example usage: test_pipeline(tmp_path) without return types