Simple interactive cli made in python

interactive_cli.py

import sys
import os

def help():
    print("Available commands:")
    for command in commands:
        print(" - " + command)

def clear():
    os.system('cls' if os.name == 'nt' else 'clear')

commands = {
    "help": help,
    "exit": sys.exit,
    "clear": clear
}

while True:
    command = input("> ")

    if command in commands:
        commands[command]()
    else:
        print("Invalid command.")