5. 於 macOS 使用 Python
***********************

This document aims to give an overview of macOS-specific behavior you
should know about to get started with Python on Mac computers. Python
on a Mac running macOS is very similar to Python on other Unix-derived
platforms, but there are some differences in installation and some
features.

There are various ways to obtain and install Python for macOS. Pre-
built versions of the most recent versions of Python are available
from a number of distributors. Much of this document describes use of
the Pythons provided by the CPython release team for download from the
python.org website. See Alternative Distributions for some other
options.


5.1. Using Python for macOS from "python.org"
=============================================


5.1.1. 安裝步驟
---------------

For current Python versions (other than those in "security" status),
the release team produces a **Python for macOS** installer package for
each new release. A list of available installers is available here. We
recommend using the most recent supported Python version where
possible. Current installers provide a universal2 binary build of
Python which runs natively on all Macs (Apple Silicon and Intel) that
are supported by a wide range of macOS versions, currently typically
from at least **macOS 10.13 High Sierra** on.

The downloaded file is a standard macOS installer package file
(".pkg"). File integrity information (checksum, size, sigstore
signature, etc) for each file is included on the release download
page. Installer packages and their contents are signed and notarized
with "Python Software Foundation" Apple Developer ID certificates to
meet macOS Gatekeeper requirements.

For a default installation, double-click on the downloaded installer
package file. This should launch the standard macOS Installer app and
display the first of several installer windows steps.

[圖片]

Clicking on the **Continue** button brings up the **Read Me** for this
installer. Besides other important information, the **Read Me**
documents which Python version is going to be installed and on what
versions of macOS it is supported. You may need to scroll through to
read the whole file. By default, this **Read Me** will also be
installed in "/Applications/Python 3.13/" and available to read
anytime.

[圖片]

Clicking on **Continue** proceeds to display the license for Python
and for other included software. You will then need to **Agree** to
the license terms before proceeding to the next step. This license
file will also be installed and available to be read later.

[圖片]

After the license terms are accepted, the next step is the
**Installation Type** display. For most uses, the standard set of
installation operations is appropriate.

[圖片]

By pressing the **Customize** button, you can choose to omit or select
certain package components of the installer. Click on each package
name to see a description of what it installs. To also install support
for the optional experimental free-threaded feature, see Installing
Free-threaded Binaries.

[圖片]

In either case, clicking **Install** will begin the install process by
asking permission to install new software. A macOS user name with
"Administrator" privilege is needed as the installed Python will be
available to all users of the Mac.

When the installation is complete, the **Summary** window will appear.

[圖片]

Double-click on the **Install Certificates.command** icon or file in
the "/Applications/Python 3.13/" window to complete the installation.

[圖片]

This will open a temporary **Terminal** shell window that will use the
new Python to download and install SSL root certificates for its use.

[圖片]

If "Successfully installed certifi" and "update complete" appears in
the terminal window, the installation is complete. Close this terminal
window and the installer window.

預設安裝會包含：

* 會有一個 "Python 3.13" 資料夾在你的 "Applications" 資料夾中。在這裡
  你可以找到 **IDLE**，它是作為官方 Python 發行版標準組成的開發環境；
  以及 **Python Launcher**，它負責處理在 Finder 中雙擊 Python 腳本的操
  作。

* "/Library/Frameworks/Python.framework" 框架，包括 Python 可執行檔案
  (executable) 和函式庫 (library)。安裝程式將此位置新增到 shell 路徑。
  要解除安裝 Python ，你可以移除這三個東西。Python 可執行檔案的符號連
  結 (symlink) 則放在 "/usr/local/bin/" 中。

備註:

  Recent versions of macOS include a **python3** command in
  "/usr/bin/python3" that links to a usually older and incomplete
  version of Python provided by and for use by the Apple development
  tools, **Xcode** or the **Command Line Tools for Xcode**. You should
  never modify or attempt to delete this installation, as it is Apple-
  controlled and is used by Apple-provided or third-party software.
  If you choose to install a newer Python version from "python.org",
  you will have two different but functional Python installations on
  your computer that can co-exist. The default installer options
  should ensure that its **python3** will be used instead of the
  system **python3**.


5.1.2. 如何執行 Python 腳本
---------------------------

There are two ways to invoke the Python interpreter. If you are
familiar with using a Unix shell in a terminal window, you can invoke
"python3.13" or "python3" optionally followed by one or more command
line options (described in 命令列與環境). The Python tutorial also has
a useful section on using Python interactively from a shell.

You can also invoke the interpreter through an integrated development
environment. IDLE --- Python 編輯器與 shell is a basic editor and
interpreter environment which is included with the standard
distribution of Python. **IDLE** includes a Help menu that allows you
to access Python documentation. If you are completely new to Python,
you can read the tutorial introduction in that document.

There are many other editors and IDEs available, see 編輯器與 IDE for
more information.

To run a Python script file from the terminal window, you can invoke
the interpreter with the name of the script file:

   "python3.13" "myscript.py"

從 Finder 執行你的腳本時，你可以：

* 把它拖曳到 **Python Launcher**

* 透過 Finder Info 視窗選擇 **Python Launcher** 作為開啟腳本（或任何
  ".py" 腳本）的預設應用程式，然後雙擊腳本。**Python Launcher** 有各種
  用來控制腳本啟動方式的選項。拖曳選項可以讓你一次更改多個選項，或使用
  其 "Preferences" 選單以全域性地更改內容。

Be aware that running the script directly from the macOS Finder might
produce different results than when running from a terminal window as
the script will not be run in the usual shell environment including
any setting of environment variables in shell profiles. And, as with
any other script or program, be certain of what you are about to run.


5.2. Alternative Distributions
==============================

Besides the standard "python.org" for macOS installer, there are
third-party distributions for macOS that may include additional
functionality. Some popular distributions and their key features:

ActivePython
   Installer with multi-platform compatibility, documentation

Anaconda
   Popular scientific modules (such as numpy, scipy, and pandas) and
   the "conda" package manager.

Homebrew
   Package manager for macOS including multiple versions of Python and
   many third-party Python-based packages (including numpy, scipy, and
   pandas).

MacPorts
   Another package manager for macOS including multiple versions of
   Python and many third-party Python-based packages. May include pre-
   built versions of Python and many packages for older versions of
   macOS.

Note that distributions might not include the latest versions of
Python or other libraries, and are not maintained or supported by the
core Python team.


5.3. 安裝額外的 Python 套件
===========================

更多資訊請見 Python Packaging User Guide。


5.4. 開發 GUI 程式
==================

於 Mac 上使用 Python 來建立 GUI 應用程式有許多選項。

標準的 Python GUI 工具套件是基於跨平臺 Tk 工具套件
(https://www.tcl.tk) 的 "tkinter"。macOS 原生版本的 Tk 有包含於安裝程
式中。

*PyObjC* 是一個 Apple Objective-C/Cocoa 框架的 Python 繫結 (binding)。
有關 PyObjC 的資訊請見 pyobjc。

有許多替代 macOS GUI 工具套件可用，包含：

* PySide：Qt GUI 工具包的官方 Python 繫結。

* PyQt：Qt 的替代 Python 繫結。

* Kivy：一個支援桌面和行動平臺的跨平臺 GUI 工具包。

* Toga：BeeWare 專案的一部分；支援桌面、行動、網頁和控制台應用程式。

* wxPython：一個支援桌面作業系統的跨平臺工具包。


5.5. 進階主題
=============


5.5.1. Installing Free-threaded Binaries
----------------------------------------

在 3.13 版被加入: （實驗性的）

備註:

  Everything described in this section is considered experimental, and
  should be expected to change in future releases.

The "python.org" Python for macOS installer package can optionally
install an additional build of Python 3.13 that supports **PEP 703**,
the experimental free-threading feature (running with the *global
interpreter lock* disabled). Check the release page on "python.org"
for possible updated information.

Because this feature is still considered experimental, the support for
it is not installed by default. It is packaged as a separate install
option, available by clicking the **Customize** button on the
**Installation Type** step of the installer as described above.

[圖片]

If the box next to the **Free-threaded Python** package name is
checked, a separate "PythonT.framework" will also be installed
alongside the normal "Python.framework" in "/Library/Frameworks". This
configuration allows a free-threaded Python 3.13 build to co-exist on
your system with a traditional (GIL only) Python 3.13 build with
minimal risk while installing or testing. This installation layout is
itself experimental and is subject to change in future releases.

Known cautions and limitations:

* The **UNIX command-line tools** package, which is selected by
  default, will install links in "/usr/local/bin" for "python3.13t",
  the free-threaded interpreter, and "python3.13t-config", a
  configuration utility which may be useful for package builders.
  Since "/usr/local/bin" is typically included in your shell "PATH",
  in most cases no changes to your "PATH" environment variables should
  be needed to use "python3.13t".

* For this release, the **Shell profile updater** package and the
  "Update Shell Profile.command" in "/Applications/Python 3.13/" do
  not support the free-threaded package.

* The free-threaded build and the traditional build have separate
  search paths and separate "site-packages" directories so, by
  default, if you need a package available in both builds, it may need
  to be installed in both. The free-threaded package will install a
  separate instance of **pip** for use with "python3.13t".

  * To install a package using **pip** without a **venv**:

       python3.13t -m pip install <package_name>

* When working with multiple Python environments, it is usually safest
  and easiest to create and use virtual environments. This can avoid
  possible command name conflicts and confusion about which Python is
  in use:

     python3.13t -m venv <venv_name>

  然後 **activate**。

* 執行 free-threaded（自由執行緒）版本的 IDLE：

     python3.13t -m idlelib

* The interpreters in both builds respond to the same PYTHON
  environment variables which may have unexpected results, for
  example, if you have "PYTHONPATH" set in a shell profile. If
  necessary, there are command line options like "-E" to ignore these
  environment variables.

* The free-threaded build links to the third-party shared libraries,
  such as "OpenSSL" and "Tk", installed in the traditional framework.
  This means that both builds also share one set of trust certificates
  as installed by the **Install Certificates.command** script, thus it
  only needs to be run once.

* If you cannot depend on the link in "/usr/local/bin" pointing to the
  "python.org" free-threaded "python3.13t" (for example, if you want
  to install your own version there or some other distribution does),
  you can explicitly set your shell "PATH" environment variable to
  include the "PythonT" framework "bin" directory:

     export PATH="/Library/Frameworks/PythonT.framework/Versions/3.13/bin":"$PATH"

  The traditional framework installation by default does something
  similar, except for "Python.framework". Be aware that having both
  framework "bin" directories in "PATH" can lead to confusion if there
  are duplicate names like "python3.13" in both; which one is actually
  used depends on the order they appear in "PATH". The "which
  python3.x" or "which python3.xt" commands can show which path is
  being used. Using virtual environments can help avoid such
  ambiguities. Another option might be to create a shell **alias** to
  the desired interpreter, like:

     alias py3.13="/Library/Frameworks/Python.framework/Versions/3.13/bin/python3.13"
     alias py3.13t="/Library/Frameworks/PythonT.framework/Versions/3.13/bin/python3.13t"


5.5.2. 使用命令列安裝
---------------------

If you want to use automation to install the "python.org" installer
package (rather than by using the familiar macOS **Installer** GUI
app), the macOS command line **installer** utility lets you select
non-default options, too. If you are not familiar with **installer**,
it can be somewhat cryptic (see **man installer** for more
information). As an example, the following shell snippet shows one way
to do it, using the "3.13.0b2" release and selecting the free-threaded
interpreter option:

   RELEASE="python-3.130b2-macos11.pkg"

   # download installer pkg
   curl -O https://www.python.org/ftp/python/3.13.0/${RELEASE}

   # create installer choicechanges to customize the install:
   #    enable the PythonTFramework-3.13 package
   #    while accepting the other defaults (install all other packages)
   cat > ./choicechanges.plist <<EOF
   <?xml version="1.0" encoding="UTF-8"?>
   <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
   <plist version="1.0">
   <array>
           <dict>
                   <key>attributeSetting</key>
                   <integer>1</integer>
                   <key>choiceAttribute</key>
                   <string>selected</string>
                   <key>choiceIdentifier</key>
                   <string>org.python.Python.PythonTFramework-3.13</string>
           </dict>
   </array>
   </plist>
   EOF

   sudo installer -pkg ./${RELEASE} -applyChoiceChangesXML ./choicechanges.plist -target /

You can then test that both installer builds are now available with
something like:

   $ # test that the free-threaded interpreter was installed if the Unix Command Tools package was enabled
   $ /usr/local/bin/python3.13t -VV
   Python 3.13.0b2 experimental free-threading build (v3.13.0b2:3a83b172af, Jun  5 2024, 12:57:31) [Clang 15.0.0 (clang-1500.3.9.4)]
   $ #    and the traditional interpreter
   $ /usr/local/bin/python3.13 -VV
   Python 3.13.0b2 (v3.13.0b2:3a83b172af, Jun  5 2024, 12:50:24) [Clang 15.0.0 (clang-1500.3.9.4)]
   $ # test that they are also available without the prefix if /usr/local/bin is on $PATH
   $ python3.13t -VV
   Python 3.13.0b2 experimental free-threading build (v3.13.0b2:3a83b172af, Jun  5 2024, 12:57:31) [Clang 15.0.0 (clang-1500.3.9.4)]
   $ python3.13 -VV
   Python 3.13.0b2 (v3.13.0b2:3a83b172af, Jun  5 2024, 12:50:24) [Clang 15.0.0 (clang-1500.3.9.4)]

備註:

  Current "python.org" installers only install to fixed locations like
  "/Library/Frameworks/", "/Applications", and "/usr/local/bin". You
  cannot use the **installer** "-domain" option to install to other
  locations.


5.5.3. 發行 Python 應用程式
---------------------------

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

* py2app：支援從 Python 專案打包成 macOS ".app"。

* Briefcase：BeeWare 專案的一部分；支援建立 macOS ".app" 的跨平台打包
  工具，亦為管理簽署和驗證 (notarization) 的工具。

* PyInstaller：一個跨平臺打包工具，可以將單一檔案或資料夾打包成可分發
  的檔案。


5.5.4. App Store Compliance
---------------------------

Apps submitted for distribution through the macOS App Store must pass
Apple's app review process. This process includes a set of automated
validation rules that inspect the submitted application bundle for
problematic code.

The Python standard library contains some code that is known to
violate these automated rules. While these violations appear to be
false positives, Apple's review rules cannot be challenged. Therefore,
it is necessary to modify the Python standard library for an app to
pass App Store review.

The Python source tree contains a patch file that will remove all code
that is known to cause issues with the App Store review process. This
patch is applied automatically when CPython is configured with the "--
with-app-store-compliance" option.

This patch is not normally required to use CPython on a Mac; nor is it
required if you are distributing an app *outside* the macOS App Store.
It is *only* required if you are using the macOS App Store as a
distribution channel.


5.6. 其他資源
=============

The python.org Help page has links to many useful resources. The
Pythonmac-SIG mailing list is another support resource specifically
for Python users and developers on the Mac.
