Abstracting rich Progress bar inside a class not working

I would like to hide the creation of a rich Progress() bars and associated tasks inside a class. I thought the following will work, but it doesn't. The progress bar doesn't render.

class Klass:

    @contextmanager
    def progress(self):
        p = Progress()
        self.Iter = p.add_task('Iterations')

        yield p
        
        p.remove_task(self.Iter)
        del self.Iter

obj = Klass()

with obj.progress() as p:
    for _ in range(100):
        sleep(0.1)
        p.advance(obj.Iter, 1)

Note that this is simplified example. In my real application, the Klass has a lot of other stuff and I need several tasks.