I'm new to Conda package management and I want to get the latest version of Python to use f-strings in my code. Currently my version is (python -V):

Python 3.5.2 :: Anaconda 4.2.0 (x86_64)

How would I upgrade to Python 3.6?

Anaconda has not updated python internally to 3.6.

a) Method 1

1. If you wanted to update you will type conda update python

2. To update anaconda type conda update conda

3. If you want to upgrade between major python version like 3.5 to 3.6, you'll have to do

    conda install python=$pythonversion$
   

b) Method 2 - Create a new environment (Better Method)

conda create --name py36 python=3.6

c) To get the absolute latest python(3.6.5 at time of writing)

conda create --name py365 python=3.6.5 --channel conda-forge

You can see all this from here

Also, refer to this for force upgrading

EDIT: Anaconda now has a Python 3.6 version here