I download the get-pip.py from <https://pip.pypa.io/en/stable/installing/> . Then i changed path in: system-variable environment into : C:\Python27\ArcGIS10.3\Lib\site-packages
after that i tried to run in from the cmd and this is the result:

[![enter image description here](https://i.stack.imgur.com/emDPN.jpg)](https://i.stack.imgur.com/emDPN.jpg)