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こんなものがあったとは…
Python2.2.3 Documents Library Reference :2.1 Build-in functions より

property([fget[, fset[, fdel[, doc]]]])

    Return a property attribute for new-style classes (classes that derive from object).
    fget is a function for getting an attribute value, likewise fset is a function for setting, and 

fdel a function for del'ing, an attribute. Typical use is to define a managed attribute x:
class C(object):

    def getx(self): return self.__x

    def setx(self, value): self.__x = value

    def delx(self): del self.__x

        x = property(getx, setx, delx, "I'm the 'x' property.")
    New in version 2.2.