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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 _add_goterms(self, go2obj_user, goid):
 """Add alt GO IDs to go2obj subset, if requested and relevant."""

        goterm = self.go2obj_orig[goid]
        if goid != goterm.id and goterm.id in go2obj_user and goid not in go2obj_user:
            go2obj_user[goid] = goterm