Overriding SSL verification in Python Launcher

I was running into a frustrating issue when trying to download a bunch of nltk test corpora in Python Launcher: the launcher kept saying it could verify my SSL certificate, which meant that I was unable to download the materials I wanted. 

It turns out that the way around this problem is as follows:

1. Create an unverified SSL context

>>> import ssl
>>> ssl._create_default_https_context = ssl._create_unverified_context

2. Then run the download

>>> import nltk
>>> nltk.download()

3. Download the packages in Launcher