我做的质数计算器

import turtle
import time
__Pen = turtle.Pen()
c = 0
_E8_8C_83_E5_9B_B4, a = int(turtle.numinput('质数计算', '请输入范围', 100, 2)), 2
start = time.clock()
print('2')
for __count in range(_E8_8C_83_E5_9B_B4):
a += 1
c = 0
b = 2
for __count in range((a - 2)):
if (a % b == 0):
c += 1
break
b += 1
if (c == 0):
print(a)
end = time.clock()
print('用时：')
print((end - start))