prob=ProblemDetails(type="http://www.ietf.org/rfc/rfc2396.txt",instance="http://www.ietf.org/rfc/rfc2396.txt",title="Internal Server Error",status=500,detail=detail,cause=cause,invalid_params=[{"param":"","reason":""}],supported_features="fffff")
# BEFORE: prob = ProblemDetails(title="Internal Server Error", status=500, detail=detail, cause=cause)