code: def test_additional_gatherers():
      @host_info_gatherer("hello")
      def get_hello():
          return "hello world"
  
      experiment = Experiment(
          "ator3000", additional_host_info=[get_hello]
      )
  
      @experiment.main
      def foo():
          pass
  
      experiment.run()
      assert experiment.current_run.host_info["hello"] == "hello world"
  
imports: from sacred import Ingredient
  from mock import patch
  import pytest
  import sys
  from sacred import cli_option
  from sacred import host_info_gatherer
  from sacred.experiment import Experiment
  from sacred.utils import apply_backspaces_and_linefeeds, ConfigAddedError, SacredError
label_desc: Use image node_id 22 for calling a global function with example usage: test_additional_gatherers() and returns: str