How do I make an argument with unknown n number of values stored in an array when parsed using docopt

I want a command line argument to be in an array format.

i.e

myprogram.py -a 1,2,4,5

and when the argument is parsed using docopt, I want to see:

{'a' = [1,2,4,5]}  # the length of this array could be as long as user may like.

I don't know if this is possible or not. If not what is the best adjustment I could make?

You will not get docopt to do this, as the comma separated list is just considered a optional argument. But you could easily do it yourself afterwards:

"""
Example of program with many options using docopt.

Usage:
  myprogram.py -a NUMBERS

Options:
  -h --help            show this help message and exit
  -a NUMBERS           Comma separated list of numbers
"""

from docopt import docopt

if __name__ == '__main__':
    args = docopt(__doc__, version='1.0.0rc2')
    args['-a'] = [int(x) for x in args['-a'].split(',')]
    print(args)