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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def init_app(self, app):
 """Initialize actions with the app or blueprint. :param app: the Flask application or blueprint object :type app: :class:`~flask.Flask` or :class:`~flask.Blueprint` Examples:: api = Api() api.init_app(blueprint) """

        try:
            # Assume this is a blueprint and defer initialization
            if app._got_registered_once is True:
                raise ValueError("""Blueprint is already registered with an app.""")
            app.record(self._deferred_blueprint_init)
        except AttributeError:
            self._init_app(app)
        else:
            self.blueprint = app