Writes devices' status to a file.

devices.py

import sys

files = ['lamp.txt', 'tv.txt', 'computer.txt']
device_number = int(sys.argv[1])
state = int(sys.argv[2])

#checks if the device number given is valid.
def check_devnum():

    return 0 < device_number < 3

#checks if state is valid.
def check_state():

    return state == 0 or state == 1

#writes state to file.
def write_config(destination, state):

    # WARNING: the next line will discard the file's contents.
    f = open(destination, 'w')
    f.write('state='+str(state))
    f.close()
    print("Done.")

if check_devnum() and check_state():

    file_name = files[device_number]
    write_config(file_name, state)

    elif not check_state():
        print("Invalid state.")

    elif not check_devnum():
        print("Invalid device number.")

    else:
        print("Invalid device number and state.")