1. Install Python 3
I bet the current Python version on your Mac is 2.X.
python -V # "2.7.10" on my Mac (macOS Sierra)
If so, let's install Python 3.
brew install python3
In brew install log, I think you saw some instructions about setting PATH to your ~/.bash_profile. I did that like this.
export PATH=~/Library/Python/3.6/bin:$PATH
Then you can use Python 3 with python3.
* Note that you can still use Python 2 with python.
python -V # You can still use Python 2
python3 -V
2. Check if you can use pip3
pip3 is a package management tool for Python 3, like npm for Node.js, gem for Ruby, and is automatically installed when you install Python 3.
Run this.
pip3 -V