Pause a thread/ execfile()

[Babloo]

i have a small python application with GUI (frontend) which has
various functions. I have a "RUN" button which runs python scripts in
the background . It basically calls execfile() function internally
which runs in a thread ,  to run the python script .

I want to implement a "PAUSE" feature which would pause the running
python script . So do that i have to either pause the thread in which
execfile() runs or pause execfile itself .

When the user presses "RUN" again then the python script should resume
running .


Any ideas how to pause the thread / pause execfile() . Any other ideas
for the same would be helpful .

Thanks