一个改进的小要求--限定随机数的个数，生成的随机数总和在一定范围内

import random

time_seconds = 18000
time_seconds_float = 1800

number = 500

print "this range of limit is between %s and %s" % (time_seconds, time_seconds + time_seconds_float)
while True:
        time_list  = [random.randint(10, 70) for i in range(500)]
        print 'sum of time_list:', sum(time_list) 
        if sum(time_list) > time_seconds and sum(time_list) < time_seconds + time_seconds_float:
            break

print "length of time_list:",len(time_list)
print time_list