dest set to string 'no_location', default as boolean False and help as a string "Don't write '#: filename:line' lines.". call the method parser.add_argument with 5 arguments: string '--no-obsolete', action as a string 'store_true',
parser . add_argument ( '--no-obsolete' , action = 'store_true' , dest = 'no_obsolete' , default = False , help = "Remove obsolete message strings." )