How to use the pywebpush.WebPushException function in pywebpush

def process_record(self, new, old=None):
        new = super(Subscription, self).process_record(new, old)
        try:
            WebPusher(new)
        except WebPushException as e:
            raise http_error(HTTPBadRequest(),
                             errno=ERRORS.INVALID_PARAMETERS,
                             message='Invalid subscription: %s' % e)
        return new

Send a webpush message asynchronously
    """
    if not WEB_PUSH_ENABLED:
        return False

    json_data = json.dumps(data)

    try:
        webpush(
            subscription_info=subscription_info,
            data=json_data,
            vapid_private_key=VAPID_PRIVATE_KEY,
            vapid_claims=VAPID_CLAIMS,
        )
        return True
    except WebPushException as error:
        logger.error(error)
        # Mozilla returns additional information in the body of the response.
        if error.response and error.response.json():
            logger.error(error.response.json())
        return False
    except TypeError as error:
        logger.error(error)
        raise error

endpoint_domain = urlparse(subscription_spec['endpoint']).netloc
    try:
        result = webpush(
            subscription_info=subscription_spec,
            data=message_json,
            timeout=10,
            **vapid_params
        )

        pipe.send({
            'subscription': subscription_id,
            'endpoint_domain': endpoint_domain,
            'result_status': str(result.status_code),
            'result_message': result.text or None
        })
    except WebPushException as err:
        pipe.send({
            'subscription': subscription_id,
            'endpoint_domain': endpoint_domain,
            'result_status': 'WebPush Exception',
            'result_message': str(err)
        })
    except ConnectTimeout as err:
        pipe.send({
            'subscription': subscription_id,
            'endpoint_domain': endpoint_domain,
            'result_status': 'Connection Timeout',
            'result_message': str(err)
        })

try:
               webpush(
                   subscription_info={
                    "endpoint": registration.endpoint,
                    "keys": {
                      "p256dh": registration.authKey,
                      "auth": registration.authSecret
                     }
                   },
                   data="",
                   vapid_private_key="./private_key.pem",
                   vapid_claims={
                    "sub": "mailto:YourNameHere@example.org",
                   }
               )
            except WebPushException as ex:
                print(ex)
                return
    return

try:
		response = webpush(
			subscription_info=subscription_info,
			data=message,
			vapid_private_key=get_manager().get_wp_private_key(application_id),
			vapid_claims=get_manager().get_wp_claims(application_id).copy(),
			**kwargs
		)
		results = {"results": [{}]}
		if not response.ok:
			results["results"][0]["error"] = response.content
			results["results"][0]["original_registration_id"] = response.content
		else:
			results["success"] = 1
		return results
	except WebPushException as e:
		raise WebPushError(e.message)

webpush_settings = getattr(settings, 'WEBPUSH_SETTINGS', {})
    vapid_private_key = webpush_settings.get('VAPID_PRIVATE_KEY')
    vapid_admin_email = webpush_settings.get('VAPID_ADMIN_EMAIL')

    # Vapid keys are optional, and mandatory only for Chrome.
    # If Vapid key is provided, include vapid key and claims
    if vapid_private_key:
        vapid_data = {
            'vapid_private_key': vapid_private_key,
            'vapid_claims': {"sub": "mailto:{}".format(vapid_admin_email)}
        }

    try:
        req = webpush(subscription_info=subscription_data, data=payload, ttl=ttl, **vapid_data)
        return req
    except WebPushException as e:
        # If the subscription is expired, delete it.
        if e.response.status_code == 410:
            subscription.delete()
        else:
            # Its other type of exception!
            raise e

try:
           webpush(
               subscription_info={
                "endpoint": registration.endpoint,
                "keys": {
                  "p256dh": registration.authKey,
                  "auth": registration.authSecret
                 }
               },
               data="",
               vapid_private_key="./private_key.pem",
               vapid_claims={
                "sub": "mailto:YourNameHere@example.org",
               }
           )
        except WebPushException as ex:
            print(ex)
            return Response("", 404)
    return ""

async def send_web_push(subscription_information, message_body):
    claims = dict(settings.VAPID_CLAIMS)
    try:
        return webpush(
            subscription_info=subscription_information,
            data=message_body,
            vapid_private_key=settings.VAPID_PRIVATE_KEY,
            vapid_claims=claims,
        )
    except WebPushException as ex:
        logger.exception("Exception while trying to send push notification")

        if ex.response and ex.response.json():
            extra = ex.response.json()
            logger.info(
                "Remote service replied with a %s:%s, %s",
                extra.code,
                extra.errno,
                extra.message,
            )
        return None