A solution to the 1st Euler Challenge

Euler1

#Find the sum of all the multiples of 3 or 5 below 1000.

"""I will define function mult() which returns true
if it's argument is divisible by 3 or 5."""

def mult(x):
    if x%3==0:
        return True
    elif x%5==0:
        return True
    else:
        return False
sum=0
for i in range(1000):
    if mult(i):
        sum+=i
print(sum)