How to use a timer in Python?

[Nico Grubert]

Hi there,

on a Linux machine running Python 2.3.5. I want to create a file 
'newfile' in a directory '/tmp' only if there is no file 'transfer.lock' 
in '/temp'.
A cronjob creates a file 'transfer.lock' in '/temp' directory every 15 
minutes while the cronjob is doing something. This job takes around 30 
seconds. During these 30 seconds the 'transfer.lock' file is present in 
the '/temp' directory and I must not create 'newfile'. After the cronjob 
has been finished, the 'transfer.lock' file is deleted from '/temp' and 
I can create 'newfile'.
How can I use a timer that waits e.g. 10 seconds if 'transfer.lock' is 
present and then checks again if 'transfer.lock' is still there?

I want to do something like this:

import os
if 'transfer.lock' in os.listdir('/temp'):
   # ...wait 10 seconds and then check again if
   # 'transfer.lock' is in os.listdir('/temp')
else:
   # create 'newfile'


Nico