How can i set default value to a widget, if it must be looked up from a database?

 

---
class ISomething(annotate.TypedInterface):
    
    def doSomething(
        self,
        ctx = annotate.Context(),
        foo = annotate.String(default="this string must be taked from a database at  render time" ),
        ):
        """Do Something Really Exciting
---