5. Utilisation de Python sur un Mac

Auteur:

Bob Savage <bobsavage@mac.com>

Python on a Mac running macOS is in principle very similar to Python on any other Unix platform, but there are a number of additional features such as the integrated development environment (IDE) and the Package Manager that are worth pointing out.

5.1. Getting and Installing Python

macOS used to come with Python 2.7 pre-installed between versions 10.8 and 12.3. You are invited to install the most recent version of Python 3 from the Python website. A current "universal2 binary" build of Python, which runs natively on the Mac's new Apple Silicon and legacy Intel processors, is available there.

Vous obtiendrez un certain nombre de choses après installation :

  • A Python 3.11 folder in your Applications folder. In here you find IDLE, the development environment that is a standard part of official Python distributions; and Python Launcher, which handles double-clicking Python scripts from the Finder.

  • A framework /Library/Frameworks/Python.framework, which includes the Python executable and libraries. The installer adds this location to your shell path. To uninstall Python, you can remove these three things. A symlink to the Python executable is placed in /usr/local/bin/.

Note

On macOS 10.8-12.3, the Apple-provided build of Python is installed in /System/Library/Frameworks/Python.framework and /usr/bin/python, respectively. You should never modify or delete these, as they are Apple-controlled and are used by Apple- or third-party software. Remember that if you choose to install a newer Python version from python.org, you will have two different but functional Python installations on your computer, so it will be important that your paths and usages are consistent with what you want to do.

IDLE includes a Help menu that allows you to access Python documentation. If you are completely new to Python you should start reading the tutorial introduction in that document.

Si vous êtes familier avec Python sur d'autres plateformes Unix, vous devriez lire la section sur comment exécuter des scripts Python depuis un shell Unix.

5.1.1. Comment exécuter un script Python

Your best way to get started with Python on macOS is through the IDLE integrated development environment; see section L'IDE and use the Help menu when the IDE is running.

If you want to run Python scripts from the Terminal window command line or from the Finder you first need an editor to create your script. macOS comes with a number of standard Unix command line editors, vim nano among them. If you want a more Mac-like editor, BBEdit from Bare Bones Software (see https://www.barebones.com/products/bbedit/index.html) are good choices, as is TextMate (see https://macromates.com). Other editors include MacVim (https://macvim.org) and Aquamacs (https://aquamacs.org).

Pour exécuter votre script depuis la fenêtre Terminal, vous devez vous assurer que /usr/local/bin est dans le chemin de recherche de votre shell (PATH).

Pour exécuter votre script depuis le Finder vous avez deux options :

  • Drag it to Python Launcher.

  • Select Python Launcher as the default application to open your script (or any .py script) through the finder Info window and double-click it. Python Launcher has various preferences to control how your script is launched. Option-dragging allows you to change these for one invocation, or use its Preferences menu to change things globally.

5.1.2. Lancer des scripts avec une interface graphique

Avec les anciennes versions de Python, il y a une bizarrerie propre à macOS dont vous devez être au courant : les programmes qui communiquent avec le gestionnaires de fenêtres Aqua (en d'autres termes, tout ce qui a une interface graphique) doivent être exécutés de façon spécifique. Utilisez pythonw au lieu de python pour exécuter ce genre de scripts.

Avec Python 3.9, vous pouvez utiliser python ou pythonw.

5.1.3. Configuration

Python on macOS honors all standard Unix environment variables such as PYTHONPATH, but setting these variables for programs started from the Finder is non-standard as the Finder does not read your .profile or .cshrc at startup. You need to create a file ~/.MacOSX/environment.plist. See Apple's Technical Q&A QA1067 for details.

For more information on installation Python packages, see section Installation de paquets Python additionnels.

5.2. L'IDE

Python ships with the standard IDLE development environment. A good introduction to using IDLE can be found at https://www.hashcollision.org/hkn/python/idle_intro/index.html.

5.3. Installation de paquets Python additionnels

This section has moved to the Python Packaging User Guide.

5.4. GUI Programming

Il y a plusieurs options pour construire des applications avec interface graphique sur le Mac avec Python.

PyObjC est un binding Python vers le framework Objective-C/Cocoa d'Apple, qui est la base de la plupart des développements modernes sur Mac. Des informations sur PyObjC sont disponible à https://pypi.org/project/pyobjc/.

La boîte à outils standard de Python pour des interfaces graphique est tkinter, basé sur la boite à outils multiplateformes Tk (https://www.tcl.tk). Une version native Aqua de Tk est empaquetée avec OS X par Apple, et la dernière version peut être téléchargée et installée depuis https://www.activestate.com ; elle peut aussi être construite depuis les sources.

A number of alternative macOS GUI toolkits are available:

  • PySide: Official Python bindings to the Qt GUI toolkit.

  • PyQt: Alternative Python bindings to Qt.

  • Kivy: A cross-platform GUI toolkit that supports desktop and mobile platforms.

  • Toga: Part of the BeeWare Project; supports desktop, mobile, web and console apps.

  • wxPython: A cross-platform toolkit that supports desktop operating systems.

5.5. Distributing Python Applications

A range of tools exist for converting your Python code into a standalone distributable application:

  • py2app: Supports creating macOS .app bundles from a Python project.

  • Briefcase: Part of the BeeWare Project; a cross-platform packaging tool that supports creation of .app bundles on macOS, as well as managing signing and notarization.

  • PyInstaller: A cross-platform packaging tool that creates a single file or folder as a distributable artifact.

5.6. Autres ressources

The Pythonmac-SIG mailing list is an excellent support resource for Python users and developers on the Mac:

https://www.python.org/community/sigs/current/pythonmac-sig/

Une autre ressource utile est le wiki MacPython :

https://wiki.python.org/moin/MacPython