Get GOA basename for a specific species. Ex: goa_human.gaf

def get_basename(self, species, ext='gaf', item=None):
        """Get GOA basename for a specific species. Ex: goa_human.gaf"""
        assert ext in self.exts, " ".join(self.exts)
        if species == 'uniprot':
            species = 'uniprot_all' if item != 'gcrp' else 'uniprot_gcrp'
        if item is None:
            return 'goa_{SPECIES}.{EXT}'.format(SPECIES=species, EXT=ext)
        assert item in self.species_items
        return 'goa_{SPECIES}_{ITEM}.{EXT}'.format(SPECIES=species, ITEM=item, EXT=ext)