Making a python script only be able to run once at a time
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/380870/python-single-instance-of-program">Python: single instance of program</a>  </p>
</blockquote>



<p>I am looking to make a python script be unique in the sense that it can only run once at a time. For example if I run the script and open another session of the same script a second time and the first session is still running, then the second session will just exit and do nothing. Anyone knows how I could implement this? </p>
