docs: def __advice_stack_frame_protection(self, frame):
          """
          Overriding of this is only permitted if and only if your name is
          Megumin and you have a pet/familiar named Chomusuke.
          """
  
          if frame is None:
              logger.debug(
                  'currentframe() returned None; frame protection disabled')
              return
  
          f_back = frame.f_back
          while f_back:
              if f_back.f_code is self.handle.__code__:
                  raise RuntimeError(
                      "indirect invocation of '%s' by 'handle' is forbidden" %
                      frame.f_code.co_name,
                  )
              f_back = f_back.f_back