calling another python file within python

[Kevin]

i have a python file called pyq which outputs stock quotes, currently i 
also have a html file that takes stock ticker inputs, i would like to 
bridge the two by building another program that takes the html inputs 
and uses them to call the pyq stock ticker program and then output them 
into a text file...

any idea how to do this? my tentative code is:



#!/usr/bin/python

import os
import urllib
os.system("python pyq.py ibm > text1.txt")




note: currently the text1.txt outputted is just blank, however if i run 
the command normally as 'python pyq.py ibm' in the command line, it 
works correctly and gives me the price of ibm.