Return GO IDs, Sections/GOs, or None.

def internal_get_goids_or_sections(self):
        """Return GO IDs, Sections/GOs, or None."""
        if self.goids_fin:
            chk_goids(self.goids_fin, "read_goids")
            return {'goids' : self.goids_fin}
        else:
            # Convert dict into 2D list retaining original section order
            sections_2d = []
            for section_name in self.sections_seen:
                if section_name in self.section2goids:
                    goids = self.section2goids.get(section_name)
                    chk_goids(goids, "GO IDs IN SECTION({S})".format(S=section_name))
                    sections_2d.append((section_name, goids))
            return {'sections' : sections_2d}