code: def update_webhook(self, scaling_group, policy, webhook, name=None,
              metadata=None):
          
          uri = "/%s/%s/policies/%s/webhooks/%s" % (self.uri_base,
                  utils.get_id(scaling_group), utils.get_id(policy),
                  utils.get_id(webhook))
          if not isinstance(webhook, AutoScaleWebhook):
              # Received an ID
              webhook = self.get_webhook(scaling_group, policy, webhook)
          body = {"name": name or webhook.name,
                  "metadata": metadata or webhook.metadata,
                  }
          resp, resp_body = self.api.method_put(uri, body=body)
          webhook.reload()
          return webhook
docs: Updates the specified webhook. One or more of the parameters may be
          specified.