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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 find_by_ref(self, ref_type, ref_id):
 """ Returns an object of type "item", "status" or "task" as a stream object. This is useful when a new status has been posted and should be rendered directly in the stream without reloading the entire stream. For details, see: https://developers.podio.com/doc/stream/get-stream-object-80054 """

        return self.transport.GET(url='/stream/%s/%s' % (ref_type, ref_id))