Multiples of 3 or 5

DESCRIPTION:

If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.

Finish the solution so that it returns the sum of all the multiples of 3 or 5 below the number passed in. Additionally, if the number is negative, return 0 (for languages that do have them).

Note: If the number is a multiple of both 3 and 5, only count it once.

---

def solution(number):
    if number<0:
        return 0
    alist=[]
    for i in range(number):
        if i%3==0 or i%5==0:
            alist.append(i)
    print(alist)
    return sum(alist)