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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 natural_key(self):
 """ Return the natural key for this object. (This is a generic implementation of the standard Django function) """

        # Recursively extract properties from related objects if needed
        vals = [reduce(getattr, name.split('__'), self)
                for name in self.get_natural_key_fields()]
        return vals