Recently, Python.org sites stopped supporting TLS version 1.0 and 1.1, which could be causing the chicken-and-egg problem you are facing. Try upgrading pip without using pip:
curl https://bootstrap.pypa.io/get-pip.py | python
Recently, Python.org sites stopped supporting TLS version 1.0 and 1.1, which could be causing the chicken-and-egg problem you are facing. Try upgrading pip without using pip:
curl https://bootstrap.pypa.io/get-pip.py | python