Return GODag object. Initialize, if necessary.

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)