code: def test_credits(util):
      credit_file = (
          "# This is a comment\n"
          "# The next line says : leave 4 blank lines\n"
          ".blank 2\n"
          "\n"
          "..Executive Story Editor\n"
          "MARCEL DURAND\n"
          "\n"
          ".blank 2\n"
          "\n"
          "..Associate Producers\n"
          "MARTIN MARCEL\n"
          "DIDIER MARTIN\n"
          "\n"
          "..Music Supervisor\n"
          "JEAN DIDIER\n"
      )
  
      file_location = os.path.join(util.TMP_DIR, "credits.txt")
      vid_location = os.path.join(util.TMP_DIR, "credits.mp4")
      with open(file_location, "w") as file:
          file.write(credit_file)
  
      image = CreditsClip(
          file_location,
          600,
          gap=100,
          stroke_color="blue",
          stroke_width=5,
          font=util.FONT,
      )
      image = image.with_duration(3)
      image.write_videofile(vid_location, fps=24, logger=None)
      assert image.mask
      assert os.path.isfile(vid_location)
  
imports: import importlib
  import math
  import os
  import shutil
  import sys
  import numpy
  import pytest
  from moviepy.audio.AudioClip import AudioClip, CompositeAudioClip
  from moviepy.audio.fx.multiply_volume import multiply_volume
  from moviepy.audio.tools.cuts import find_audio_period
  from moviepy.video.compositing.concatenate import concatenate_videoclips
  from moviepy.video.fx.loop import loop
  from moviepy.video.fx.time_mirror import time_mirror
  from moviepy.video.io.VideoFileClip import VideoFileClip
  from moviepy.video.tools.credits import CreditsClip
  from moviepy.video.tools.cuts import FramesMatch, FramesMatches, detect_scenes, find_video_period
  from moviepy.video.tools.drawing import circle, color_gradient, color_split
  from moviepy.video.tools.interpolators import Interpolator, Trajectory
  from moviepy.video.VideoClip import BitmapClip, ColorClip, ImageClip, VideoClip
label_desc: Use image node_id 1 for calling a global function with example usage: test_credits(util) without return types