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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 to_cloudformation(self):
 """Generates CloudFormation resources from a SAM API resource :returns: a tuple containing the RestApi, Deployment, and Stage for an empty Api. :rtype: tuple """


        rest_api = self._construct_rest_api()
        deployment = self._construct_deployment(rest_api)

        swagger = None
        if rest_api.Body is not None:
            swagger = rest_api.Body
        elif rest_api.BodyS3Location is not None:
            swagger = rest_api.BodyS3Location

        stage = self._construct_stage(deployment, swagger)
        permissions = self._construct_authorizer_lambda_permission()

        return rest_api, deployment, stage, permissions