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Functions & basics

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How to Build a Subcommand Parser Tree with argparse in Python

Create a CLI with nested subcommands (like git) using argparse subparsers, where each subcommand maps to its own handler function.

argparse cli subparsers
Python 
import argparse


def cmd_add(args):
    print(f"Adding {args.num1} + {args.num2} = {args.num1 + args.num2}")


def cmd_sub(args):
    print(f"Subtracting {args.num1} - {args.num2} = {args.num1 - args.num2}")


def main():
    parser = argparse.ArgumentParser(prog="calculator")
    subparsers = parser.add_subparsers(d…
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