Ctree is available from GitHub and must be built from source:
$ git clone git@github.com:ucb-sejits/ctree.git
$ cd ctree
$ python setup.py install
To verify your installation, install nose:
$ pip install nose
And run nosetests:
$ nosetests
......................................................................
....S...............................................S.S...............
......................................................................
......
----------------------------------------------------------------------
Ran 216 tests in 1.220s
OK (SKIP=3)