def primenumber():
memo = [True for _ in range(1001)]
memo[0], memo[1] = False, False
for i in range(2, 1001):
if memo[i]:
for j in range(i*2, 1001, i):
memo[j]=False

return [i for i in range(2, 1001) if memo[i]]

print(primenumber())

これで