Link to the assignment and link to the class.
I have compiled different versions of the brown corpus as a numpy matrix for various context window sizes. For the sake of the current assignment, they can be downloaded here.
Since matplotlib has issues with virtualenv, copy the 'frameworkpython' to the 'bin' directory of your venv and use it to run your scripts. Depending on your Python version, you may have to make some alterations to the script.