How to use the patroni.watchdog.base.WatchdogError function in patroni

def get_support(self):
        if self._support_cache is None:
            info = watchdog_info()
            try:
                self._ioctl(WDIOC_GETSUPPORT, info)
            except (WatchdogError, OSError, IOError) as e:
                raise WatchdogError("Could not get information about watchdog device: {}".format(e))
            self._support_cache = WatchdogInfo(info.options,
                                               info.firmware_version,
                                               bytearray(info.identity).decode(errors='ignore').rstrip('\x00'))
        return self._support_cache

def keepalive(self):
        try:
            os.write(self._fd, b'1')
        except OSError as e:
            raise WatchdogError("Could not send watchdog keepalive: {0}".format(e))

def _ioctl(self, func, arg):
        """Runs the specified ioctl on the underlying fd.

        Raises WatchdogError if the device is closed.
        Raises OSError or IOError (Python 2) when the ioctl fails."""
        if self._fd is None:
            raise WatchdogError("Watchdog device is closed")
        if os.name != 'nt':
            import fcntl
            fcntl.ioctl(self._fd, func, arg, True)

def open(self):
        try:
            self._fd = os.open(self.device, os.O_WRONLY)
        except OSError as e:
            raise WatchdogError("Can't open watchdog device: {0}".format(e))

def get_timeout(self):
        timeout = ctypes.c_int()
        try:
            self._ioctl(WDIOC_GETTIMEOUT, timeout)
        except (WatchdogError, OSError, IOError) as e:
            raise WatchdogError("Could not get timeout on watchdog device: {}".format(e))
        return timeout.value