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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 drag_drop_cb(self, viewer, urls):
 """Punt drag-drops to the ginga shell. """

        channel = self.fv.get_current_channel()
        if channel is None:
            return
        self.fv.open_uris(urls, chname=channel.name, bulk_add=True)
        return True