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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 fill_altgoids(go2obj):
 """Given a go2obj containing key GO IDs, fill with all alternate GO IDs."""

    alt2obj = {altgo:goobj for goobj in go2obj.values() for altgo in goobj.alt_ids}
    for goid, goobj in alt2obj.items():
        go2obj[goid] = goobj