From Python Script in Pycharm, call another Python Script and run it in Parallel 

I am running a tkinter GUI, I have created buttons to run various scripts, but when I run them the GUI beachballs and is unaccessible.    How can I call these scripts and still be able to operate the GUI ??

i am trying to use subprocess:

subprocess.Popen(["python", "stock.py"])

but I get the following error:

Traceback (most recent call last):
File "stock_scrape.py", line 2, in <module>
from selenium import webdriver
ImportError: No module named selenium

Any ideas ??

Thanks

Manolo