I'm not so sure... I assume you're referring to this line: Return host, serialized, ":", and port concatenated. ...except if the port is an empty string,

I'm not so sure... I assume you're referring to this line: Return host, serialized, ":", and port concatenated. ...except if the port is an empty string, the process will terminate one step sooner: If port is the empty string, return host, serialized. So there would be no trailing colon, in that case.