Control a RPI vehicle with one letter commands

maze.py

import RPi.GPIO as GPIO
from time import sleep

GPIO.setwarnings(False)
GPIO.setmode(GPIO.BCM)

MOTOR1 = 14
MOTOR2 = 18
MOTOR3 = 24
MOTOR4 = 12
GPIO.setup(MOTOR1, GPIO.OUT)
GPIO.setup(MOTOR2, GPIO.OUT)
GPIO.setup(MOTOR3, GPIO.OUT)
GPIO.setup(MOTOR4, GPIO.OUT)

while True:
   inputString = raw_input()
   if inputString == "w":
      GPIO.output(MOTOR1, True)
      GPIO.output(MOTOR2, True)
      GPIO.output(MOTOR3, True)
      GPIO.output(MOTOR4, True)
   elif inputString == "s":
      GPIO.output(MOTOR1, False)
      GPIO.output(MOTOR2, False)
      GPIO.output(MOTOR3, False)
      GPIO.output(MOTOR4, False)
   elif inputString == "a":
      GPIO.output(MOTOR1, False)
      GPIO.output(MOTOR2, True)
      GPIO.output(MOTOR3, False)
      GPIO.output(MOTOR4, True)
   elif inputString == "d":
      GPIO.output(MOTOR1, True)
      GPIO.output(MOTOR2, False)
      GPIO.output(MOTOR3, True)
      GPIO.output(MOTOR4, False)
   elif inputString == "exit":
      break
   else:
      print("I don't understand that command")

GPIO.cleanup()