Change to `Creates` as function is now singular.

IPython/core/magics/osm.py

@@ -98,7 +98,7 b' class OSMagics(Magics):'
           /usr/local/lf9560/bin:/usr/local/intel/compiler70/ia32/bin:...
 
         You can use the alias facility to acess all of $PATH.  See the %rehashx
-        function, which automatically create aliases for the contents of your
+        function, which automatically creates aliases for the contents of your
         $PATH.
 
         If called with no parameters, %alias prints the current alias table."""