Changing your Python version with Anaconda | downgrade/upgrade python version on conda
First, make sure you have the latest version of conda by running
conda update conda
Then run
conda install python=3.5.0 # or maybe conda install python=2.7.8 # or whatever you want....
This will attempt to update all your packages in your root environment to Python 3 versions. If it is not possible (e.g., because some package is not built for Python 3.5), it will give you an error message indicating which package(s) caused the issue.
If you installed packages with pip, you’ll have to reinstall them.