Python script that do a dd of 1k on /dev/random 10 times and tell the wasted time

entropy.py

import subprocess
import os
import timeit
import time

def read_dev_random():
    devnull = open(os.devnull, 'w')
    subprocess.check_call(['dd', 'if=/dev/random', 'of=mytmp', 'bs=1k', 'count=1'],stdout=devnull, stderr=devnull)


iterations = 10
iteration_times = []

for i in range(iterations):
    iteration_time = timeit.timeit(read_dev_random, number=1)
    print "Period for iterations %d is %.3f" % (i, iteration_time)
    iteration_times.append(iteration_time)
    
average = sum(iteration_times) / float(iterations)
print "Average time reading random bytes from /dev/random %.3f seconds over %d iterations" % (average, iterations)