Hi there,
We found there is one inconsistency between the official aws doc and the actual api response for AWS::ApiGateway::RestApi.
Per the doc, the type of policy is a json object(https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-apigateway-restapi.html#cfn-apigateway-restapi-body):

But the actual return result is a string:

I am wondering which one we should follow. Please take a look and have a right fix.
Thanks