from __future__ import generators not working in IDLE

[Grace]

"from __future__ import generators" does not work in IDLE which is included
in Python 2.2a1.

See the copy&pasted text from the real IDLE running:

>>> from __future__ import generators
>>>
>>> <string>:2: Warning: 'yield' will become a reserved keyword in the
future
<string>:2: Warning: 'yield' will become a reserved keyword in the future
<string>:2: Warning: 'yield' will become a reserved keyword in the future
def f():
 yield 1

SyntaxError: invalid syntax
>>>

Is there any workarounds?

Thanks in advance.

Grace.