python is not recognized as an internal or external command

I have found the answer... click on the installer and check the box "Add python to environment variables" DO NOT uninstall the old one rather click on modify....Click on link for picture...

Try "py" instead of "python" from command line:

C:\Users\Cpsa>py
Python 3.4.1 (v3.4.1:c0e311e010fc, May 18 2014, 10:38:22) [MSC v.1600 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
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