Mark intern() move as done.

pep-3100.txt

@@ -178,7 +178,7 @@ To be removed:
 * ``coerce()``: no longer needed [2]_
 * ``execfile()``, ``reload()``: use ``exec()`` [2]_
 * ``input()``: use ``eval(sys.stdin.readline())`` [2]_ [done]
-* ``intern()``, ``id()``: put in ``sys`` (?) [2]_, [22]_
+* ``intern()``: put in ``sys`` [2]_, [22]_ [done]
 * ``map()``, ``filter()``: use list comprehensions instead??? [1]_, [9]_
   (Actually these can stay.)
 * ``reduce()``: write a loop instead [2]_, [9]_ [done]