Recently I was trying to install requests python package and it gave the error you can see above. This was annoying as I was hoping it would be simple. It seems I needed to install/update a couple of other packages first, this were pyopenssl and Cryptography.
I could see I had them installed, and checked the version they were too low. If you need to check the version you can type pip show pyopenssl.
Once I saw the versions, a simple update would upgrade them, to do this the commands were
sudo pip update pyopenssl -U
sudo pip install Cryptography -U
Once this was done I could install requests, hope this helps.
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