@coroutine_next not working in Listing 4-46

[heywiki]

https://github.com/jython/book/blob/master/DefiningFunctionsandUsingBuilt-Ins.rst

I've tried Listing 4-46 where Decorators in Coroutines are declared, but i get

$ jython co_example.py
Traceback (most recent call last):
  File "co_example.py", line 2, in <module>
    @coroutine_next
NameError: name 'coroutine_next' is not defined

Added my code here: https://github.com/heywiki/jython-book-examples/blob/master/chapter4/co_example.py