python求第1000个素数

#Problem Set 1
#Name: Jeff Chen
#Description:Write a program that computes and prints the 1000th prime number.
#Date:2012-6-22

from math import *
i=0   
for num in range(1,10000):
    isprime=True
    for j in range(2,int(sqrt(num))+1):
        if num%j==0&num!=j:
            isprime=False
            break
    if isprime:
        i=i+1
    if i>1000: 
        break
print num