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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 _init_goslims(self, dagslim):
 """Get GO IDs in GO slims."""

        go2obj_main = self.gosubdag.go2obj
        go2obj_slim = {go for go, o in dagslim.items() if go in go2obj_main}
        if self.gosubdag.relationships:
            return self._get_goslimids_norel(go2obj_slim)
        return set(dagslim.keys())