python，如何使参数接受参数组合？

Question

I did see another post on making python args accept multiple inputs but I don't think that applies to my question here.

I have a script that executes using command line and I made an argument where I could input a model and based on the model, my script will update a file for me that I can use in another program (this is for codeml.ctl file for PAML in case anyone is interested).

I execute the script as:

python my_script.py -g=geneA.phy -t=treefile.phy -M="0 1 2 3"

But sometimes I may want to rerun just one model so:

-M=0

Or perhaps I want to rerun two random models

-M="0 3"

In my python script, I have it setup so based on the model input for my -M flag, I edit lines in the control file.

def main():
    parser = argparse.ArgumentParser(description="Update codeml.ctl file using model names")
    parser.add_argument('-M', '--modeltype', type=str)
    parser.add_argument('-g', '--genefile', type=str)
    parser.add_argument('-t', '--treefile', type=str)
    args = parser.parse_args()

def lines_to_replace(args):
    replace_seq = args.genefile
    replace_treefile = args.treefile
    replace_outfile = args.genefile.split(".phy")[0] + "_OUT"

def model(args):
    for index, line in enumerate(fileinput.input('codeml.ctl', inplace=1)):
        if args.modeltype == '0 1 2 3':
             if index == 30:
                 line = "Model is 0 1 2 3"; print(line)
        if args.modeltype == '0 1 2':
             if index == 30:
                 line = "Model is 0 1 2"; print(line)

And I would do this but this is tedious and I cannot figure out a way for my args.modeltype to accept a combination of model inputs. The actual file only takes model inputs with spaces in between and it has to be on one line. It would have to be something like:

 if args.modeltype == ???:
      if index == 30:
           line = "Model is" + str(???); print(line)

Combinations always confuse me. Would something like *args work for this, but then how would I parse *args? Perhaps using user input and saving that as a variable would work? I've never used that before but I will try it.

---

Edit to be more clear:

I want my model argument to accept arguments from this list of models [0, 1, 2, 3]. I can just type 0, or I could type "0 1" or even "2 3" and the script should execute and update the model line (index == 30) appropriately. However, if I type "9 99" that is wrong because those models don't exist. The suggestions below work where I use nargs="+" and then " ".join(args.model), but this still accepts incorrect input. Is there a way to input the list of accepted models into my parser.add_argument('model', type='str', nargs='+', help='Input model').

Answer 1

If you replaced your -M argument with the following:

parser.add_argument('models', metavar='N', type=int, nargs='+',
                help='list of models to run')

then args.models would be a list of the models you specified, as in

python my_script.py -g=geneA.phy -t=treefile.phy 0 1 2 3

would result in args.models being ['0', '1', '2', '3'] , which you can then do whatever you want with (to be honest, your question is not at all clear on what you want done with this information).