Command line arguments, options and flags can be created using

• sys.argv (older)
• argparse (newer) (this article)

You can:

• Pass in options (also known as key value pairs)
• Pass in flags (True boolean)

Here is a basic example that will create command line options and flags.

• action="store" is used to create an option (key value pair)
• action="store_true" is used to create a flag that contains a value of True (boolean)

#!/usr/bin/python3
import argparse
parser = argparse.ArgumentParser()
parser.add_argument("-e", "--environment", action="store",      required=False, default="lab", choices=['lab', 'development', 'staging', 'production'])
parser.add_argument("-v", "--validate",    action="store_true", required=False, help="run this script in validation mode")
args = parser.parse_args()

if args.validate:
  print(f"args.validate = {args.validate}")

print(f"args.environment = {args.environment}")