gistfile1.py

import os
import time
import subprocess

def create_commits(path):
    os.chdir(path)
    for i in xrange(1, 10):
        start = time.clock()
        subprocess.call('dd if=/dev/urandom of=testfile_1MB bs=1024 count=1', shell=True)
        subprocess.call('cat testfile_1MB >> testfile_500MB', shell=True)
        subprocess.call('rm testfile_1MB', shell=True)
        subprocess.call('git commit -am"' + str(i) + '"', shell=True)

def checkout(path, commit):
    os.chdir(path)
    subprocess.call('git reset --hard ' + commit, shell=True)

def main():
    create_commits('/Users/andy/Desktop/test1/')

if __name__ == '__main__':
    main()