Doc:Install or build>Install>MacOS: Update the Python installation instructions [MacOS]

hugo/content/installation/install/macos/_index.md

@@ -60,18 +60,20 @@ $ sudo port select --set python python36
 
 ### Configure Python for BornAgain
 
-To make your Python installation aware of BornAgain, you have to install the BornAgain libraries into the `site-packages` of Python.
-This can be done by running the `bornagain_install_python.py` script from the application bundle. Assuming that BornAgain is installed in the
-`/Applications/BornAgain.app` folder, launch the Terminal application and run the following command:
+To make your Python installation aware of BornAgain, you have to install the BornAgain
+libraries into the `site-packages` of Python.
+This can be done by using the Python package ('wheel') included in the application bundle.
+Assuming that BornAgain is installed in the `/Applications/bornagain.app` folder, launch
+the Terminal application and run the following command (note that the location and name
+of the wheel depends on the BornAgain and Python versions and the platform):
 
 ```
-$ python /Applications/BornAgain.app/Contents/libexec/BornAgain-{{< release-string-short >}}/bornagain_python_install.py
+$ python3 -m pip install /Applications/bornagain.app/Contents/python/3.9/wheel/BornAgain.whl
 ```
 
-During the execution of the script, just select the default options by pressing the enter key.
-This script will install the BornAgain libraries into the site-packages of the given Python interpreter.
+For further options, see the official [pip's documentation](https://pip.pypa.io/en/stable).
 
-Now check that the installation went successfully by typing
+Finally, verify that the installation by typing
 
 ```
 $ python -c "import bornagain"