Convert String to Message Data Type

Hi, is this an outdated answer perhaps? If I try this code I get an error:

“Attribute localizes is not allowed on local variables.”

TrueMessage<localizes>:message = "True"
Popup.SetDescriptionText(TrueMessage)

If I take out <localizes> I get a different error:

This variable expects to be initialized with a value of type message, but this initializer is an incompatible value of type []char.