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I guess you need a -dev package as well .. It is asking for a header file

I'm not seeing openssl-dev provided by MacPorts. I removed the PGK version of Python. Then:

$ sudo port install python35
$ sudo port install py35-readline
$ sudo port select --set python3 python35
$ make install-user

Now I get:

ImportError: No module named 'pip'

I guess I should wait for the Electron version of Pison, right? :D