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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __setAttributeDefaults(self):
 """Looks for default values for unset attributes. If class variable representing attribute is None, then it must be defined as an instance variable. """

        for k,v in self.__class__.attributes.items():
            if v is not None and self.attributes.has_key(k) is False:
                if isinstance(v, types.FunctionType):
                    self.attributes[k] = v(self)
                else:
                    self.attributes[k] = v