Patch to document the changes detailed in https://github.com/amoffat/sh/issues/269

index.rst.patch

--- index.txt   2015-08-24 22:48:41.587933500 +0200
+++ index.txt.new       2015-08-24 22:41:03.269527000 +0200
@@ -381,6 +381,20 @@
        print(myserver.tail("/var/log/dumb_daemon.log", n=100))
 
 
+.. _special_arguments_defaults:
+
+Special arguments defaults
+--------------------------
+
+You can set the default values of all the :ref:`special keyword argument <special_arguments>`,
+by using the `defaults` context manager:
+
+    import sh, sys
+    with sh.defaults(_out=sys.stdout):
+        from sh import echo
+    echo('HELLO WORLD!')  # prints to stdout
+
+
 .. _with_contexts:
 
 'With' contexts