Document use of python methods in jinja

doc/topics/jinja/index.rst

@@ -1700,6 +1700,23 @@ Will insert the following message in the minion logs:
 
 .. jinja_ref:: custom-execution-modules
 
+Python methods
+====================
+
+A power feature of jinja that is only hinted at in the official jinja
+documentation is that you can use the native python methods of the
+variable type. Here is the python documentation for `string methods`_.
+
+.. code-block:: jinja
+
+  {% set hostname,domain = grains.id.partition('.')[::2] %}{{ hostname }}
+
+.. code-block:: jinja
+
+  {% set strings = grains.id.split('-') %}{{ strings[0] }}
+
+.. _`string methods`: https://docs.python.org/2/library/stdtypes.html#string-methods
+
 Custom Execution Modules
 ========================