On MAC OS you can simply find the location of python/python3 by using the command which python or which python3. (works for Linux too)

And it should give something like:

For python

/usr/local/bin/python

For python3

/Library/Frameworks/Python.framework/Versions/3.9/bin/python3

Export the path to your bash_profile

In your terminal type

sudo nano ~/.bash_profile

Enter your password and paste the following lines

PYTHONPATH="/Library/Frameworks/Python.framework/Versions/3.9/bin/python3"
export PYTHONPATH

Press control + x to exit, and press y for saving on being asked to save

Press `enter' to return to terminal window

Source it using the following command in terminal, run

source ~/.bash_profile

Path to python3 should be updated now!!

If you set up environment variables from the terminal command it gets erased as soon as you close that terminal. To set up and keep them you have to update them in .bash_profile file which resides in the home directory as a hidden file. Follow the below commands to update it.

Open terminal

cd ~  

(To take you to the home directory of the mac)

open -a "Visual Studio Code" .bash_profile 

( To open .bash_profile file, in the place of "Visual Studio Code" you can use any text editor name)

Now, .bash_profile will be opened and there you can set your environment variables and save it.

Example:

NUM_SAS_WORKERS=10

Now run echo $[NUM_SAS_WORKERS] in terminal to read that

After performing the above steps some times still environment variables not available to read in your python project/file. In such cases, you have to restart or log off and log in to your machine that can fix the issue.

To check whether the environment variable is available to your python code run the below script in your python console. This should print all your environment variables.

import os 
print(os.eviron)