code: def get_validated_path(filename, compression_fn=None):
      if compression_fn is not None:
          validated_path = f"{filename}.{compression_fn_map[compression_fn]['extension']}"
      else:
          validated_path = filename
      return validated_path
  
label_desc: Use image node_id 4 for calling a global function with example usage: get_validated_path(filename, compression_fn) and returns: validated_path