install modules for different versions of python
There are different versions python with pip on my macbook, when run a python scripts, it prompted as,
ModuleNotFoundError: No module named 'regex'
actually I had install the ‘regex’ module by pip,
it is not in the place that python can found it.
after search, it is resolved by execute the command as following
$ where pip
/usr/local/bin/pip
$ where python3
/Library/Frameworks/Python.framework/Versions/3.8/bin/python3
$python3 -m pip install regex
