cstutoringcenter.com_Happy Numbers

def sum_of_digits(num):
    sum = 0
    for x in str(num):
        sum += int(x) ** 2
    return sum

def happy(num):
    while True:
        num = sum_of_digits(num)
        if num == 4: return False
        if num == 1: return True
sum = 0
for x in xrange(1,300001):
    if happy(x):sum += 1
print sum