https://davidsword.ca/a-cheaper-diy-status-light/ - Raspberry Pi control a common anode or common cathode RGB LED. e sure to know the difference of your RGB LED. Usage: `python3 rgb-led-status.py <avaliable|busy|offline>` to set as green, red, or off respectively.

rgb-led-status.py

# https://davidsword.ca/a-cheaper-diy-status-light/

import sys
import RPi.GPIO as GPIO

GPIO.setwarnings(False)

# Note this is BOARD numbering.
GPIO.setmode(GPIO.BOARD)
redPin   = 3
greenPin = 5
bluePin  = 7

# set to false if using a RGB LED with common Anode.
commonCath = True

GPIO.setup(redPin,   GPIO.OUT, initial=0)
GPIO.setup(greenPin, GPIO.OUT, initial=0)
GPIO.setup(bluePin,  GPIO.OUT, initial=0)

if commonCath:
    setOn = 1
    setOff = 0
else:
    setOn = 0
    setOff = 1

def turnOn(pin):
    GPIO.output(pin, setOn)
    
def turnOff(pin):
    GPIO.output(pin, setOff)
    
def main():
    cmd = sys.argv[1]

    if cmd == "busy":
        turnOff(greenPin)
        turnOn(redPin)
    elif cmd == "available":
        turnOn(greenPin)
        turnOff(redPin)
    elif cmd == "offline":
        turnOff(greenPin)
        turnOff(redPin);
    else:
        print("Not a valid command")

main()