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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 _openapi_json(self):
 """Serve JSON spec file"""

        # We don't use Flask.jsonify here as it would sort the keys
        # alphabetically while we want to preserve the order.
        from pprint import pprint
        pprint(self.to_dict())
        return current_app.response_class(json.dumps(self.to_dict(), indent=4),
                                          mimetype='application/json')