Raspberry Pi LED Morse code script

morse.py

#!/usr/bin/python
import RPi.GPIO as gpio
import sys, time

def blink(pin, duration):
    gpio.output(pin, gpio.HIGH)
    time.sleep(0.4 * duration)
    gpio.output(pin, gpio.LOW)
    time.sleep(0.4)

morse = {
    'a': [1, 3],
    'b': [3, 1, 1, 1],
    'c': [3, 1, 3, 1],
    'd': [3, 1, 1],
    'e': [1],
    'f': [1, 1, 3, 1],
    'g': [3, 3, 1],
    'h': [1, 1, 1, 1],
    'i': [1, 1],
    'j': [1, 3, 3, 3],
    'k': [3, 1, 3],
    'l': [1, 3, 1, 1],
    'm': [3, 3],
    'n': [3, 1],
    'o': [3, 3, 3],
    'p': [1, 3, 3, 1],
    'q': [3, 3, 1, 3],
    'r': [1, 3, 1],
    's': [1, 1, 1],
    't': [3],
    'u': [1, 1, 3],
    'v': [1, 1, 1, 3],
    'w': [1, 3, 3],
    'x': [3, 1, 1, 3],
    'y': [3, 1, 3, 3],
    'z': [3, 3, 1, 1],
    ' ': [4],
}

def main(msg):
    gpio.setmode(gpio.BOARD)
    gpio.setup(11, gpio.OUT)

    try:
        for char in msg:
            print(char)
            if char in morse:
                for beep in morse[char]:
                    blink(11, beep)
            time.sleep(0.8)
    finally:
        gpio.cleanup()

if len(sys.argv) == 2:
    main(sys.argv[1])
else:
    print("usage: morse.py [input string]")

Connect an LED to pin 11 (+) and pin 9 (-) with a resistor between 11 and the LED. Run this script as root and pass a message in as the only parameter to see it blinked out in Morse code.