def main():

    parser = argparse.ArgumentParser(description="Simulation of drivers' behavior")
    parser.add_argument('-f', '--fleet',
                        help='Fleet sizes to simulate, formatted as comma-separated list (i.e. "-f 250,275,300")')
    parser.add_argument('-m', '--multiplier',
                        help='Surge multiplier, formatted as comma-separated list (i.e. "-m 1,1.5,2")')

    args = parser.parse_args()
    if args.fleet:
        fleet_sizes = [int(x) for x in args.fleet.split(',')]
    else:
        fleet_sizes = FLEET_SIZE
    if args.multiplier:
        surges = [float(x) for x in args.multiplier.split(',')]
    else:
        surges = [SURGE_MULTIPLIER]

python script.py -f 1000, 1500 -m 1, 2

for i in {1000, 1500}; do python script.py -f i & done; done

ValueError: could not convert string to float: 'i'