w1, w2, w3 = 0.3, 0.2, 0.5

kanto = [73, 67, 43]
johnto = [ 92, 88, 64]
hoen = [81, 154 , 58]
sinnoh = [102, 43, 37]
unova = [ 69 ,96 , 70]

weights = [w1 ,w2 ,w3]

def crop_yield(region, weights):
    result = 0
    for x, w in zip(region , weights):
        result += x*w
    return result    

crop_yield(kanto, weights)