code: def cache_fname(img, backend, light, cache_dir, sat=""):
      
      color_type = "light" if light else "dark"
      file_name = re.sub("[/|\\|.]", "_", img)
      file_size = os.path.getsize(img)
  
      file_parts = [file_name, color_type, backend,
                    sat, file_size, __cache_version__]
      return [cache_dir, "schemes", "%s_%s_%s_%s_%s_%s.json" % (*file_parts,)]
docs: Create the cache file name.