python – How can I manipulate parser arguments

please find the code below

if __name__ == '__main__':
    global_command = argparse.ArgumentParser()
    subparser = global_command.add_subparsers(
    dest='subparser_name', help='...')

#we add parser for the partionner and the arguments
partionner_command = subparser.add_parser('partitioned_edf',  help ='adding parser')
partionner_command.add_argument('file', help='input file', type=argparse.FileType('r'))
partionner_command.add_argument('h', help='heuristic')
partionner_command.add_argument('ff|wf|bf|nf', help='first fit')
partionner_command.add_argument('s', help='sort')
partionner_command.add_argument('du|iu', help='decreasing utilization')
partionner_command.add_argument('l', help='limits')
partionner_command.add_argument('limit', type= int, help='positive integer,the time step limit for simulation')
partionner_command.add_argument('m', help='the number of identical cores')
partionner_command.add_argument('cores', type= int, help='positive integer, the number of identical cores')

#namespace takes the arguments
namespace = global_command.parse_args()

if namespace.subparser_name is None:
    from sys import stderr
elif namespace.subparser_name == 'partitioned_edf':

After that elif I want to make cases depending on the third argument (if we have ff, wf, bf or nf in the console).