SHELL

pipenv not found after pip3 install

# macOS
$ brew install pipenv

# linux 
$ sudo -H pip install -U pipenv
# or
$ sudo pip install pipenv

# powershell

pip install pipenv
py -m pip install pipenv

pipenv not found

First, remove your current version of virtualenv: pip uninstall virtualenv
Then, remove your current version of pipenv: pip uninstall pipenv
When you are asked Proceed (y/n)? just enter y. This will give you a clean slate.
Finally, you can once again install pipenv and its dependencies: pip install pipenv
Check installation with pipenv --versio