Log rotation script. This script would be called by cron at fixed intervals.

log_rotate.py

from os.path import getsize
from os import rename
from datetime import datetime

srcnames = ['./logfile1', './logfile2']

kb = 1024
mb = kb * 1024

def log_rotate():
  for srcname in srcnames:
    size = getsize(srcname)
    if size > 10 * mb :
      dstname = srcname + "." + datetime.now().strftime('%Y%m%d%H%M%S')
      rename(srcname, dstname)

if __name__ == '__main__':
  log_rotate()