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Python Object-Oriented Python Advanced Objects Proper Properties

Posted by Andrew McLane
Andrew McLane
3,385 Points

def area(self):

So when I just return self.length * self.width, the code works. However, when I assign self.area to the area calculation, the code doesn't work. Was wondering why this is?

rectangle.py 
class Rectangle:
    def __init__(self, width, length):
        self.width = width
        self.length = length

    @property
    def area(self):
        self.area = self.width * self.length
        return self.area

1 Answer

Clayton Perszyk
MOD
Clayton Perszyk
Treehouse Moderator 48,850 Points
Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 48,850 Points

Hi Andrew,

You can't have an attribute with the same name as a property / method. if you change self.area to something like self._area, it will work. However, you should declare the attribute (self._area) in the initializer.

class Rectangle:
    def __init__(self, width, length):
        self.width = width
        self.length = length
        self._area = None

    @property
    def area(self):
        self._area = self.width * self.length
        return self._area
Andrew McLane
Andrew McLane
3,385 Points

thanks!