curl https://pyenv.run | bash

WARNING: seems you still have not added 'pyenv' to the load path.

# Load pyenv automatically by adding
# the following to ~/.bashrc:

export PATH="$HOME/.pyenv/bin:$PATH"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"

pyenv install --list | grep " 3\.[6789]"

pyenv install -v 3.7.2
pyenv install -v 3.9.1