Change the link to Magic Methods from its GitHub repo to its pdf file directly.

Author: hector12free

docs/intro/learning.rst

@@ -210,7 +210,7 @@ and can make classes and objects behave in different and magical ways.
 
     `A Guide to Python's Magic Methods <http://www.rafekettler.com/magicmethods.html>`_
 Note: The Rafekettler.com is currently down, you can go to their Github version directly. Here you can find a PDF version:
-    `A Guide to Python's Magic Methods (repo on GitHub) <https://github.com/RafeKettler/magicmethods>`_
+    `A Guide to Python's Magic Methods (repo on GitHub) <https://github.com/RafeKettler/magicmethods/blob/master/magicmethods.pdf>`_
 
 
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