[split] serious n00b.. NLTK in python 2.7 and 3.5

[snippsat]

You could have mention that you use Mac.
Doing it Right

Homebrew installs pip3 for you.
pip3 is the alias to pip pointing to the Homebrew’d Python 3.

I would mention pyenv the best version management to use,
and safe it do not mess with system Python installation.

Examle Linux,work the same on Mac.

# Install
mint@mint ~ $ pyenv install 3.6.4
Downloading Python-3.6.4.tar.xz...
-> https://www.python.org/ftp/python/3.6.4/Python-3.6.4.tar.xz
Installing Python-3.6.4...
Installed Python-3.6.4 to /home/mint/.pyenv/versions/3.6.4

# Set python and pip to point to 3.6.4
mint@mint ~ $ pyenv global 3.6.4
mint@mint ~ $ python -V
Python 3.6.4
mint@mint ~ $ pip -V
pip 9.0.1 from /home/mint/.pyenv/versions/3.6.4/lib/python3.6/site-packages (python 3.6)
# Finish