2021 Python PIP Could not find a version that satisfies the requirement pip<21.0

reason

This kind of problem is due to domestic network restrictions that can’t connect to the specified download address. You need to configure a domestic acceleration source.

solve

$ cd ~
$ mkdir .pip
$ cd .pip
$ vim pip.conf

pip.conf content

[global]
timeout = 6000
index-url = http://pypi.douban.com/simple
trusted-host = http://pypi.douban.com