Need help with reading lines etc.

[woah123]

I'm given a text document with marks and course codes, and I need to create a function where you input the directory of the file, and the course code. Doing so, the code will return the average mark of all the marks in the text with that course code. Any ideas?

[woooee]

First read http://www.daniweb.com/software-development/computer-science/threads/573/we-only-give-homework-help-to-those-who-show-effort
then see if it is the same homework problem as
http://www.daniweb.com/software-development/python/threads/439588/python-data-extraction-help
or
http://www.daniweb.com/software-development/python/threads/439504/converting-a-list-to-a-a-string-of-integers

[woah123]

It's similar to those posts, but for me I have to write a function like this
def avg(file,code):
The user has to input the directory of the file, and the course code. The code that I have to write will return the average of all the marks with that course code in the file.