Helper for building forward referenced flow task.
Therationaly is ability to specify referencies to the class attribute and methods before they declated.
this is like a self but for the class body.
The referencies are resolved by the metaclass at the end of the flow construction.
class MyFlow(Flow): start = ( flow.StartFunction(this.start_flow) .Next(this.task) ) task = ( flow.View(MyView) .Assign(this.start.owner) .Next(this.end) ) end = flow.End() def start_flow(self, activation): activation.prepare() activation.done()