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How to use argparse

📅 2013-Feb-20 ⬩ ✍️ Ashwin Nanjappa ⬩ 🏷️ argparse, python ⬩ 📚 Archive

The argparse module makes it really easy to read, parse and use the input arguments passed to a Python program.


Usage is in 3 simple steps:


Here is a simple program that illustrates usage of argparse with different types of input arguments:

import argparse
import sys

def print_args(args):
    print args

    print "Radius:   ", args.rad
    print "Distance: ", args.d
    print "Name:     ",
    print "Recompute:", args.recompute
    print "In files: ", args.in_files

def main():

    # Create parser
    arg_parser = argparse.ArgumentParser(
        description="This program achieves nothing!",

    # Add arguments you want to handle
    modes = ["release", "debug"]
    arg_parser.add_argument("--radius", type=float, default=1.2, required=True, help="Radius of the component")
    arg_parser.add_argument("-d", type=int, default=9, help="Distance to the component")
    arg_parser.add_argument("--name", type=str, help="Name of component")
    arg_parser.add_argument("--mode", type=str, choices=modes, help="Mode to use. Should be either release or debug")
    arg_parser.add_argument("--recompute", action="store_true", default=False, help="Indicate if recomputation is needed")
    arg_parser.add_argument("--in_files", type=str, nargs="+", help="One or more input file paths")

    if len(sys.argv) == 1:

    # Parse sys.argv using parser
    args = arg_parser.parse_args()

    # Pass arguments around

if __name__ == "__main__":


This call has many useful options, the only one I actually use is:


This call has many useful options. Many of them are needed in most scripts:

Tried with: Python 3.10 and Ubuntu 22.04

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