Method __get__

src/8/lazily_computed_attributes/example1.py:4–10

(self, instance, cls)

    def __init__(self, func):
        self.func = func
    def __get__(self, instance, cls):
        if instance is None:
            return self
        else:
            value = self.func(instance)
            setattr(instance, self.func.__name__, value)
            return value
        
if __name__ == '__main__':
    import math