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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, **kwargs):
 """ Initializes the Flask-Bouncer extension for the specified application. :param app: The application. """

        self.app = app

        self._init_extension()

        self.app.before_request(self.check_implicit_rules)

        if kwargs.get('ensure_authorization', False):
            self.app.after_request(self.check_authorization)