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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 get_preview_kwargs(self, **kwargs):
 """ Gets the url keyword arguments to pass to the `preview_view` callable. If the `pass_through_kwarg` attribute is set the value of `pass_through_attr` will be looked up on the object. So if you are previewing an item Obj<id=2> and :: self.pass_through_kwarg = 'object_id' self.pass_through_attr = 'pk' This will return :: { 'object_id' : 2 } """

        if not self.pass_through_kwarg:
            return {}

        obj = self.get_object()
        return {
            self.pass_through_kwarg: getattr(obj, self.pass_through_attr)
        }