update URL

doc/tutorial/python.txt

@@ -10,7 +10,7 @@ tutorials/exercises if you need to learn it or only need a refresher:
 
   * `Python Challenge <http://www.pythonchallenge.com/>`__
   * `Dive into Python <http://diveintopython.net/>`__
-  * `Google Python Class <http://code.google.com/edu/languages/google-python-class/index.html>`__
+  * `Google Python Class <https://developers.google.com/edu/python/>`__
   * `Enthought Python course <https://training.enthought.com/?utm_source=academic&utm_medium=email&utm_campaign=EToD-Launch#/courses>`__ (free for academics)
 
 We have a tutorial on how :ref:`Python manages its memory <python-memory-management>`.