class_docstr: Helper for exit hook for testing argcomplete
code: def exit(cls, code):
      raise cls(str(code))
  
imports: import io
  import os
  import typing
  import pytest
  from traitlets import Unicode
  from traitlets.config.application import Application
  from traitlets.config.configurable import Configurable
  from traitlets.config.loader import KVArgParseConfigLoader
label_desc: Use image node_id 1 for calling the CustomError obj's underlying member method code with example usage: obj.exit(cls, code) without return types