code: def test_saving_png_file(es, tmp_path):
      output_path = str(tmp_path.joinpath("test1.png"))
  
      es.plot(to_file=output_path)
  
      assert os.path.isfile(output_path)
      os.remove(output_path)
  
file_path: featuretools/featuretools/tests/entityset_tests/test_plotting.py
imports: import os
  import re
  import graphviz
  import pandas
  import pytest
  from featuretools import EntitySet
  from featuretools.utils.gen_utils import Library
label_desc: Use image node_id 6 for calling a global function with example usage: test_saving_png_file(es, tmp_path) without return types