go.talks: go4python Guido is not responsible for mypy, and cython should be there.

R=adg
CC=golang-dev
https://golang.org/cl/23070043
diff --git a/2013/go4python.slide b/2013/go4python.slide
index c1ed696..742355c 100644
--- a/2013/go4python.slide
+++ b/2013/go4python.slide
@@ -53,7 +53,7 @@
 	// but no
 	a = 2
 
-Statically-typed Python? Check Guido's [[http://www.mypy-lang.org/][mypy]]
+Statically-typed Python? Check [[http://www.mypy-lang.org/][mypy]] and [[http://cython.org/][Cython]].
 
 * Run time pyrotechnics