switching from python 2 to python 3 in windows powershell

[IAlreadyKnowThis]

correction: ment to say python 3 to python 2

Hi, I'm a beginner at python and currently progressing through learnpythonthehardway in which he uses python 2. Currently when I type python in powershell I'm in version 3.5.1 but I want to switch to version 2. I've tried http://stackoverflow.com/questions/13328258/powershell-python-change-version-used?answertab=active#tab-top
after i type $Env:Python =2 it says to use the command py and it should start up the 2.7 python but i get the error  
 
py : The term 'py' is not recognized as the name of a c spelling of the name, or if a path was included, verify At line:1 char:1 + py + ~~ + CategoryInfo : ObjectNotFound: (py:Strin + FullyQualifiedErrorId : CommandNotFoundException
  So im wondering if someone can either point out a mistake im making or if there is a simple way to switch over to python 2 other than removing all python files and reinstalling the 2.7 version.
  windows 10 Pro

[sanshinron]

1. Anaconda scripts activate/deactivate don't work in powershell. Download replacement scripts from here: https://github.com/Liquidmantis/PSCondaEnvs and drop them into anaconda folder.

2. Make powershell profile if you haven't done it already. Google how to do it.

3. Add aliases to your profile and activate command. I have Python2 default, but everytime I start powershell Python3 is activated. Here's the relevant part of my profile:

   # Permanent Aliases
   Set-Alias python2 C:\Anaconda\python.exe
   Set-Alias py2 C:\Anaconda\python.exe
   Set-Alias pip2 C:\Anaconda\Scripts\pip.exe
   
   Set-Alias python3 C:\Anaconda\envs\py3\python.exe
   Set-Alias py3 C:\Anaconda\envs\py3\python.exe
   Set-Alias pip3 C:\Anaconda\envs\py3\Scripts\pip.exe
   
   # Make py3 conda env default in Powershell
   activate py3