nltk.download() hangs on OS X

Try running nltk.download_shell() instead as there is most likely an issue displaying the downloader UI. Running the download_shell() function will bypass it.

I had trouble with this, too, and I ended up with this workaround:

> cd /usr/lib -- change directory to the desired install directory

> sudo idle -- run the interactive interpreter as an administrator (superuser do)

At this point the system asks for your password before starting up idle. Then, within idle, the nltk.download() function works fine:

>>> nltk.download()

In my case I was running nlkt.download() in a Jupyter (IPython) notebook on a Mac, and it had opened a window BEHIND the browser window without me knowing. I finally found it by Mission Control (four fingers swipe up). That's why the function was seemingly hanging.