[Python] How does NiceGUI object binding (listener) work behind the scenes?

Here is a code example from their great documentation:

NiceGUI label

from nicegui import ui

class status_label(ui.label):
def _handle_text_change(self, text: str) -> None:
super()._handle_text_change(text)
if text == 'ok':
self.classes(replace='text-positive')
else:
self.classes(replace='text-negative')

model = {'status': 'error'}
status_label().bind_text_from(model, 'status')
ui.switch(on_change=lambda e: model.update(status='ok' if e.value else 'error'))

ui.run()


Why does this work? How do they make model reactive with assigning a whole new wrapped object to that name? I read their code but it is too highly advance for me to comprehend it.

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