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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 create_jwt_manager(self, app) -> JWTManager: """ Override to implement your custom JWT manager instance :param app: Flask app """

        jwt_manager = JWTManager()
        jwt_manager.init_app(app)
        jwt_manager.user_loader_callback_loader(self.load_user)
        return jwt_manager