adding a valid label for installation.rst to ref to

andrewmacgregor · andrewmacgregor · commit 470b548a9a30 · 2012-10-15T14:42:57.000+08:00
diff --git a/docs/starting/which-python.rst b/docs/starting/which-python.rst
@@ -1,6 +1,8 @@
 Picking an Interpreter
 ======================
 
+.. _which-python:
+
 Which Python to use?
 
 
