Twisted error

Python 2.7.3 (default, Apr 22 2013, 07:20:17)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import twisted
>>> twisted
<module 'twisted' from '/usr/lib64/python2.7/site-packages/twisted/__init__.pyc'>
>>> import twisted.words.protocols
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named words.protocols
>>>