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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_plt_data(self, hdrgos_usr):
 """Given User GO IDs, return their GO headers and other GO info."""

        hdrgo2usrgos = self.grprobj.get_hdrgo2usrgos(hdrgos_usr)
        usrgos_actual = set([u for us in hdrgo2usrgos.values() for u in us])
        go2obj = self.gosubdag.get_go2obj(usrgos_actual.union(hdrgo2usrgos.keys()))
        return hdrgo2usrgos, go2obj