resolve pip upgrade error after pip fixed it!

[Escapingbug]

pypa/pip#5599

[CCbird]

Fix the pip update:

RUN pip install -U pip
RUN echo 'from pip import main' > /usr/bin/pip
RUN echo 'if name == 'main':' >> /usr/bin/pip
RUN echo ' sys.exit(main._main())' >> /usr/bin/pip

[Escapingbug]

Can you give me a pull request on how to fix that exactly? Alghough im not sure this is permanent fix.. Or can you adjust the docker file to remove the update part and test it for me? I'm right now a little bit busy on this one, and my network is too slow to test..

[Escapingbug]

@CCbird