Divisor

def divisor(n):
#@param:
#   n: int;
#   return: Bool;
    if n==3 or n==6 or n==9:
        return True
    elif len(str(n))>1:
        n1=0
        for i in range(0,int(len(str(n)))):
            n1 += int(str(n)[i])
        return divisor(n1)
    else: return False

def test():
    from random import randint
    r = randint(0,10000)
    if r%3==0:
        print("Test random integer \nNumber:",r,"\nExpected result: True\nResult:",divisor(r))
    else:
        print("Test random integer \nNumber:",r,"\nExpected result: False\nResult:",divisor(r))