Pip3 install virtualenv

pip3 install virtualenv
Defaulting to user installation because normal site-packages is not writeable
Collecting virtualenv
  Downloading virtualenv-20.13.0-py2.py3-none-any.whl (6.5 MB)
     |████████████████████████████████| 6.5 MB 682 kB/s
Collecting platformdirs<3,>=2
  Downloading platformdirs-2.4.1-py3-none-any.whl (14 kB)
Requirement already satisfied: six<2,>=1.9.0 in /Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.8/lib/python3.8/site- packages (from virtualenv) (1.15.0) 
Collecting distlib<1,>=0.3.1
  Downloading distlib-0.3.4-py2.py3-none-any.whl (461 kB)
     |████████████████████████████████| 461 kB 1.5 MB/s
Collecting filelock<4,>=3.2
  Downloading filelock-3.4.2-py3-none-any.whl (9.9 kB)
Installing collected packages: platformdirs, distlib, filelock, virtualenv
  WARNING: The script virtualenv is installed in '/Users/YOUR_USER/Library/Python/3.8/bin' which is not on PATH.
  Consider adding this directory to PATH or, if you prefer to suppress this warning, use --no-warn-script-location.
Successfully installed distlib-0.3.4 filelock-3.4.2 platformdirs-2.4.1 virtualenv-20.13.0
WARNING: You are using pip version 20.2.3; however, version 21.3.1 is available.
You should consider upgrading via the '/Library/Developer/CommandLineTools/usr/bin/python3 -m pip install --upgrade pip' command

See also

• virtualenv, venv, .venv, .venv/, pip3 install virtualenv, virtualenv --help