def init_app(self, app):
        # type: (Flask) -> None
        """Register the extension on the given Flask application.

        Use this function only when no Flask application was provided
        in the ``app`` keyword argument to the constructor of this class.

        The function sets ``True`` defaults for
        :py:const:`VERIFY_SIGNATURE_APP_CONFIG` and
        :py:const:`VERIFY_TIMESTAMP_APP_CONFIG` configurations. It adds
        the skill id: self instance mapping to the application
        extensions, and creates a
        :py:class:`ask_sdk_webservice_support.webservice_handler.WebserviceHandler`
        instance, for request verification and dispatch.

        :param app: A :py:class:`flask.Flask` application instance
        :type app: flask.Flask
        :rtype: None
        """
        app.config.setdefault(VERIFY_SIGNATURE_APP_CONFIG, True)
        app.config.setdefault(VERIFY_TIMESTAMP_APP_CONFIG, True)

        if EXTENSION_NAME not in app.extensions:
            app.extensions[EXTENSION_NAME] = {}

        app.extensions[EXTENSION_NAME][self._skill_id] = self

        with app.app_context():
            self._create_webservice_handler(self._skill, self._verifiers)
Register the extension on the given Flask application.

        Use this function only when no Flask application was provided
        in the ``app`` keyword argument to the constructor of this class.

        The function sets ``True`` defaults for
        :py:const:`VERIFY_SIGNATURE_APP_CONFIG` and
        :py:const:`VERIFY_TIMESTAMP_APP_CONFIG` configurations. It adds
        the skill id: self instance mapping to the application
        extensions, and creates a
        :py:class:`ask_sdk_webservice_support.webservice_handler.WebserviceHandler`
        instance, for request verification and dispatch.

        :param app: A :py:class:`flask.Flask` application instance
        :type app: flask.Flask
        :rtype: None