<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _init_go2nt_aug(self, go2nt):
 """Augment go2nt with GO ID key to account for alt GO IDs."""

        go2obj = self.gosubdag.go2obj
        # Get alt GO IDs
        go2nt_aug = {}
        # NOW
        for goid_usr, nt_usr in go2nt.items():
            goobj = go2obj[goid_usr]
            if goobj.alt_ids:
                alts = set(goobj.alt_ids)
                alts.add(goobj.id)
                for goid_alt in alts:
                    if goid_alt not in go2nt:
                        go2nt_aug[goid_alt] = nt_usr
        # WAS
        # Add alt GO IDs to go2nt
        for goid, gont in go2nt_aug.items():
            go2nt[goid] = gont
        return go2nt