Add *,**,@ to index, as suggested by

http://farmdev.com/thoughts/24/what-does-the-def-star-variable-or-def-asterisk-parameter-syntax-do-in-python-/

The right entry type to use isn't clear; operator seems wrong, because *,**,@
aren't being used in expressions here.  I put them as 'statement'; 'syntax'
might be better.

Doc/reference/compound_stmts.rst

@@ -424,6 +424,9 @@ when the function is called.
 The function definition does not execute the function body; this gets executed
 only when the function is called.
 
+.. index::
+  statement: @
+
 A function definition may be wrapped by one or more :term:`decorator` expressions.
 Decorator expressions are evaluated when the function is defined, in the scope
 that contains the function definition.  The result must be a callable, which is
@@ -464,6 +467,10 @@ as the default, and explicitly test for it in the body of the function, e.g.::
        penguin.append("property of the zoo")
        return penguin
 
+.. index::
+  statement: *
+  statement: **
+
 Function call semantics are described in more detail in section :ref:`calls`. A
 function call always assigns values to all parameters mentioned in the parameter
 list, either from position arguments, from keyword arguments, or from default

Doc/tutorial/controlflow.rst

@@ -437,6 +437,9 @@ not done, the order in which the arguments are printed is undefined.
 Arbitrary Argument Lists
 ------------------------
 
+.. index::
+  statement: *  
+
 Finally, the least frequently used option is to specify that a function can be
 called with an arbitrary number of arguments.  These arguments will be wrapped
 up in a tuple.  Before the variable number of arguments, zero or more normal
@@ -464,6 +467,9 @@ or tuple::
    >>> range(*args)            # call with arguments unpacked from a list
    [3, 4, 5]
 
+.. index::
+  statement: **
+
 In the same fashion, dictionaries can deliver keyword arguments with the ``**``\
 -operator::