Initialize section_name2goids.

def get_sec2gos(sortobj):
        """Initialize section_name2goids."""
        sec_gos = []
        for section_name, nts in sortobj.get_desc2nts_fnc(hdrgo_prt=True)['sections']:
            sec_gos.append((section_name, set(nt.GO for nt in nts)))
        return cx.OrderedDict(sec_gos)