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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_main_goids(go2obj, goids):
 """Ensure main GO IDs are included in go2obj."""

    # User GO IDs (goids) may be either main GO IDs or alternate GO IDs.
    for goid in goids:
        goobj = go2obj[goid]
        # If a user specified an ALT GO ID and main GO ID not in go2obj:
        if goid != goobj.id and goobj.id not in go2obj:
            # Add main GO ID to go2obj
            go2obj[goobj.id] = goobj