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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 defaults(self, *args):
 """ Fill in a given object with default properties. """

        ns = self.Namespace
        ns.obj = self.obj

        def by(source, *ar):
            for i, prop in enumerate(source):
                if prop not in ns.obj:
                    ns.obj[prop] = source[prop]

        _.each(args, by)

        return self._wrap(ns.obj)