code: def assert_exist_and_clean(filename, msg=None):
      if not msg:
          msg = f"File {filename} does not exist"
      assert filename.exists(), msg
      filename.unlink()
  
file_path: plotnine/tests/test_save_as_pdf_pages.py
imports: import warnings
  from pathlib import Path
  import matplotlib.pyplot
  import pytest
  from plotnine import aes, geom_text, ggplot, ggtitle, theme
  from plotnine.data import mtcars
  from plotnine.exceptions import PlotnineError, PlotnineWarning
  from plotnine.ggplot import save_as_pdf_pages
label_desc: Use image node_id 3 for calling a global function with example usage: assert_exist_and_clean(filename, msg) without return types