def save
      # If we have an id, just update our fields.
      return update! if id

      from_response client.post("/webhooks", {
        description: description,
        idModel: id_model,
        callbackURL: callback_url
      })
    end
def save
      # If we have an id, just update our fields.
      return update! if id

      from_response client.post("/webhooks", {
        description: description,
        idModel: id_model,
        callbackURL: callback_url
      })
    end
Save the webhook.

 @raise  [Trello::Error] if the Webhook could not be saved.

 @return [String] the JSON representation of the saved webhook.