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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 get_godag(fin_obo="go-basic.obo", prt=sys.stdout, loading_bar=True, optional_attrs=None):
 """Return GODag object. Initialize, if necessary."""

    from goatools.obo_parser import GODag
    download_go_basic_obo(fin_obo, prt, loading_bar)
    return GODag(fin_obo, optional_attrs, load_obsolete=False, prt=prt)