<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def add_alt_goids(go2values, altgo2goobj):
 """Add alternate source GO IDs."""

    for goobj_key in altgo2goobj.values():
        values_curr = go2values[goobj_key.id]
        for goid_alt in goobj_key.alt_ids:
            go2values[goid_alt] = values_curr
    return go2values