Overriding properties in python

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The Python docs on the property decorator suggest the following idiom:

class C(object):
    def __init__(self):
        self._x = None
    @property
    def x(self):
        return self._x
    @x.setter
    def x(self, value):
        self._x = value
    @x.deleter
    def x(self):
        del self._x

And then subclasses can override a single setter/getter like this:

class C2(C):
    @C.x.getter
    def x(self):
        return self._x * -1

This is a little warty because overriding multiple methods seems to require you to do something like:

class C3(C):
    @C.x.getter
    def x(self):
        return self._x * -1
    # C3 now has an x property with a modified getter
    # so modify its setter rather than C.x's setter.
    @x.setter 
    def x(self, value):
        self._x = value * 2

Of course at the point that you’re overriding getter, setter, and deleter you can probably just redefine the property for C3.

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