docs: def Heartbeat(self):
      """Writes a heartbeat to the registry."""
      service_key = _GetServiceKey()
      try:
        winreg.SetValueEx(service_key, "Nanny.heartbeat", 0, winreg.REG_DWORD,
                          int(time.time()))
      except OSError as e:
        logging.debug("Failed to heartbeat nanny at %s: %s", service_key, e)