It’s important that you install Python 2.7.9 or later, since Python versions beginning with 2.7.9 include PIP, the Python library/package/software manager which is. Caution: This chapter is under repair! This chapter describes SWIG's support of Python. SWIG is compatible with most recent Python versions including Python 3.0 and.

Installing Python Unlike most Unix systems and services, Windows does not include a system supported installation of Python. To make Python available, the CPython team has compiled Windows installers (MSI packages) with every for many years. These installers are primarily intended to add a per-user installation of Python, with the core interpreter and library being used by a single user.

The installer is also able to install for all users of a single machine, and a separate ZIP file is available for application-local distributions. Installation Steps Four Python 3.6 installers are available for download - two each for the 32-bit and 64-bit versions of the interpreter. The web installer is a small initial download, and it will automatically download the required components as necessary. The offline installer includes the components necessary for a default installation and only requires an internet connection for optional features. See for other ways to avoid downloading during installation.

Removing the MAX_PATH Limitation Windows historically has limited path lengths to 260 characters. This meant that paths longer than this would not resolve and errors would result. In the latest versions of Windows, this limitation can be expanded to approximately 32,000 characters.

Your administrator will need to activate the “Enable Win32 long paths” group policy, or set the registry value HKEY_LOCAL_MACHINE SYSTEM CurrentControlSet Control FileSystem@LongPathsEnabled to 1. This allows the function, the module and most other path functionality to accept and return paths longer than 260 characters when using strings. (Use of bytes as paths is deprecated on Windows, and this feature is not available when using bytes.) After changing the above option, no further configuration is required. Installing Without UI All of the options available in the installer UI can also be specified from the command line, allowing scripted installers to replicate an installation on many machines without user interaction. These options may also be set without suppressing the UI in order to change some of the defaults. To completely hide the installer UI and install Python silently, pass the /quiet option.

To skip past the user interaction but still display progress and errors, pass the /passive option. The /uninstall option may be passed to immediately begin removing Python - no prompt will be displayed. All other options are passed as name=value, where the value is usually 0 to disable a feature, 1 to enable a feature, or a path. The full list of available options is shown below. Name Description Default InstallAllUsers Perform a system-wide installation. 0 TargetDir The installation directory Selected based on InstallAllUsers DefaultAllUsersTargetDir The default installation directory for all-user installs%ProgramFiles% Python X.Y or%ProgramFiles(x86)% Python X.Y DefaultJustForMeTargetDir The default install directory for just-for-me installs%LocalAppData% Programs PythonXY or%LocalAppData% Programs PythonXY-32 DefaultCustomTargetDir The default custom install directory displayed in the UI (empty) AssociateFiles Create file associations if the launcher is also installed.

1 CompileAll Compile all.py files to.pyc. 0 PrependPath Add install and Scripts directories tho PATH and.PY to PATHEXT 0 Shortcuts Create shortcuts for the interpreter, documentation and IDLE if installed. 1 Include_doc Install Python manual 1 Include_debug Install debug binaries 0 Include_dev Install developer headers and libraries 1 Include_exe Install python.exe and related files 1 Include_launcher Install. 1 InstallLauncherAllUsers Installs for all users. 1 Include_lib Install standard library and extension modules 1 Include_pip Install bundled pip and setuptools 1 Include_symbols Install debugging symbols ( *.pdb) 0 Include_tcltk Install Tcl/Tk support and IDLE 1 Include_test Install standard library test suite 1 Include_tools Install utility scripts 1 LauncherOnly Only installs the launcher.

This will override most other options. 0 SimpleInstall Disable most install UI 0 SimpleInstallDescription A custom message to display when the simplified install UI is used. (empty) For example, to silently install a default, system-wide Python installation, you could use the following command (from an elevated command prompt).

Python-3.6.0.exe InstallAllUsers=0 Include_launcher=0 Include_test=0 SimpleInstall=1 SimpleInstallDescription='Just for me, no test suite.' (Note that omitting the launcher also omits file associations, and is only recommended for per-user installs when there is also a system-wide installation that included the launcher.) The options listed above can also be provided in a file named unattend.xml alongside the executable. This file specifies a list of options and values. When a value is provided as an attribute, it will be converted to a number if possible.

Values provided as element text are always left as strings. This example file sets the same options and the previous example. Installing Without Downloading As some features of Python are not included in the initial installer download, selecting those features may require an internet connection. To avoid this need, all possible components may be downloaded on-demand to create a complete layout that will no longer require an internet connection regardless of the selected features. Note that this download may be bigger than required, but where a large number of installations are going to be performed it is very useful to have a locally cached copy. Execute the following command from Command Prompt to download all possible required files. Remember to substitute python-3.6.0.exe for the actual name of your installer, and to create layouts in their own directories to avoid collisions between files with the same name.

Modifying an install Once Python has been installed, you can add or remove features through the Programs and Features tool that is part of Windows. Select the Python entry and choose “Uninstall/Change” to open the installer in maintenance mode. “Modify” allows you to add or remove features by modifying the checkboxes - unchanged checkboxes will not install or remove anything.

Some options cannot be changed in this mode, such as the install directory; to modify these, you will need to remove and then reinstall Python completely. “Repair” will verify all the files that should be installed using the current settings and replace any that have been removed or modified. “Uninstall” will remove Python entirely, with the exception of the, which has its own entry in Programs and Features. Alternative bundles Besides the standard CPython distribution, there are modified packages including additional functionality. The following is a list of popular versions and their key features: Installer with multi-platform compatibility, documentation, PyWin32 Popular scientific modules (such as numpy, scipy and pandas) and the conda package manager. A “comprehensive Python analysis environment” with editors and other development tools. Windows-specific distribution with prebuilt scientific packages and tools for building packages.

Note that these packages may not include the latest versions of Python or other libraries, and are not maintained or supported by the core Python team. C: >set PATH=C: Program Files Python 3.6;%PATH% C: >set PYTHONPATH=%PYTHONPATH%;C: My_python_lib C: >python These changes will apply to any further commands executed in that console, and will be inherited by any applications started from the console. Including the variable name within percent signs will expand to the existing value, allowing you to add your new value at either the start or the end. Modifying PATH by adding the directory containing python.exe to the start is a common way to ensure the correct version of Python is launched. To permanently modify the default environment variables, click Start and search for ‘edit environment variables’, or open System properties, Advanced system settings and click the Environment Variables button.

In this dialog, you can add or modify User and System variables. To change System variables, you need non-restricted access to your machine (i.e. Administrator rights). Changed in version 3.5. Besides using the automatically created start menu entry for the Python interpreter, you might want to start Python in the command prompt. The installer has an option to set that up for you.

On the first page of the installer, an option labelled “Add Python to PATH” may be selected to have the installer add the install location into the PATH. The location of the Scripts folder is also added. This allows you to type python to run the interpreter, and pip for the package installer. Thus, you can also execute your scripts with command line options, see documentation. If you don’t enable this option at install time, you can always re-run the installer, select Modify, and enable it. Alternatively, you can manually modify the PATH using the directions in.

You need to set your PATH environment variable to include the directory of your Python installation, delimited by a semicolon from other entries. An example variable could look like this (assuming the first two entries already existed). New in version 3.3.

The Python launcher for Windows is a utility which aids in locating and executing of different Python versions. It allows scripts (or the command-line) to indicate a preference for a specific Python version, and will locate and execute that version. Unlike the PATH variable, the launcher will correctly select the most appropriate version of Python. It will prefer per-user installations over system-wide ones, and orders by language version rather than using the most recently installed version.

Python3 Re-executing the command should now print the latest Python 3.x information. As with the above command-line examples, you can specify a more explicit version qualifier. Assuming you have Python 2.6 installed, try changing the first line to #! Python2.6 and you should find the 2.6 version information printed.

Note that unlike interactive use, a bare “python” will use the latest version of Python 2.x that you have installed. This is for backward compatibility and for compatibility with Unix, where the command python typically refers to Python 2.

From file associations The launcher should have been associated with Python files (i.e..py,.pyw,.pyc files) when it was installed. This means that when you double-click on one of these files from Windows explorer the launcher will be used, and therefore you can use the same facilities described above to have the script specify the version which should be used. The key benefit of this is that a single launcher can support multiple Python versions at the same time depending on the contents of the first line. Shebang Lines If the first line of a script file starts with #!, it is known as a “shebang” line. Linux and other Unix like operating systems have native support for such lines and they are commonly used on such systems to indicate how a script should be executed. This launcher allows the same facilities to be used with Python scripts on Windows and the examples above demonstrate their use. To allow shebang lines in Python scripts to be portable between Unix and Windows, this launcher supports a number of ‘virtual’ commands to specify which interpreter to use.

The supported virtual commands are: • /usr/bin/env python • /usr/bin/python • /usr/local/bin/python • python For example, if the first line of your script starts with. /usr/bin/python The default Python will be located and used. As many Python scripts written to work on Unix will already have this line, you should find these scripts can be used by the launcher without modification. If you are writing a new script on Windows which you hope will be useful on Unix, you should use one of the shebang lines starting with /usr. Any of the above virtual commands can be suffixed with an explicit version (either just the major version, or the major and minor version) - for example /usr/bin/python2.7 - which will cause that specific version to be located and used. The /usr/bin/env form of shebang line has one further special property.

Before looking for installed Python interpreters, this form will search the executable PATH for a Python executable. This corresponds to the behaviour of the Unix env program, which performs a PATH search. Customization via INI files Two.ini files will be searched by the launcher - py.ini in the current user’s “application data” directory (i.e. The directory returned by calling the Windows function SHGetFolderPath with CSIDL_LOCAL_APPDATA) and py.ini in the same directory as the launcher.

The same.ini files are used for both the ‘console’ version of the launcher (i.e. Py.exe) and for the ‘windows’ version (i.e. Pyw.exe) Customization specified in the “application directory” will have precedence over the one next to the executable, so a user, who may not have write access to the.ini file next to the launcher, can override commands in that global.ini file).

Finding modules Python usually stores its library (and thereby your site-packages folder) in the installation directory. So, if you had installed Python to C: Python, the default library would reside in C: Python Lib and third-party modules should be stored in C: Python Lib site-packages. To completely override, create a._pth file with the same name as the DLL ( python36._pth) or the executable ( python._pth) and specify one line for each path to add to. The file based on the DLL name overrides the one based on the executable, which allows paths to be restricted for any program loading the runtime if desired. When the file exists, all registry and environment variables are ignored, isolated mode is enabled, and is not imported unless one line in the file specifies import site. Blank paths and lines starting with # are ignored. Each path may be absolute or relative to the location of the file.

Import statements other than to site are not permitted, and arbitrary code cannot be specified. Note that.pth files (without leading underscore) will be processed normally by the module. When no._pth file is found, this is how is populated on Windows: • An empty entry is added at the start, which corresponds to the current directory. • If the environment variable exists, as described in, its entries are added next. Note that on Windows, paths in this variable must be separated by semicolons, to distinguish them from the colon used in drive identifiers ( C: etc.). • Additional “application paths” can be added in the registry as subkeys of SOFTWARE Python PythonCore version PythonPath under both the HKEY_CURRENT_USER and HKEY_LOCAL_MACHINE hives.

Subkeys which have semicolon-delimited path strings as their default value will cause each path to be added to. (Note that all known installers only use HKLM, so HKCU is typically empty.) • If the environment variable is set, it is assumed as “Python Home”. Otherwise, the path of the main Python executable is used to locate a “landmark file” (either Lib os.py or pythonXY.zip) to deduce the “Python Home”. If a Python home is found, the relevant sub-directories added to ( Lib, plat-win, etc) are based on that folder. Otherwise, the core Python path is constructed from the PythonPath stored in the registry.

• If the Python Home cannot be located, no is specified in the environment, and no registry entries can be found, a default path with relative entries is used (e.g.. Plat-win, etc). If a pyvenv.cfg file is found alongside the main executable or in the directory one level above the executable, the following variations apply: • If home is an absolute path and is not set, this path is used instead of the path to the main executable when deducing the home location. The end result of all this is: • When running python.exe, or any other.exe in the main Python directory (either an installed version, or directly from the PCbuild directory), the core path is deduced, and the core paths in the registry are ignored. Other “application paths” in the registry are always read. • When Python is hosted in another.exe (different directory, embedded via COM, etc), the “Python Home” will not be deduced, so the core path from the registry is used. Other “application paths” in the registry are always read.

• If Python can’t find its home and there are no registry value (frozen.exe, some very strange installation setup) you get a path with some default, but relative, paths. For those who want to bundle Python into their application or distribution, the following advice will prevent conflicts with other installations: • Include a._pth file alongside your executable containing the directories to include. This will ignore paths listed in the registry and environment variables, and also ignore unless import site is listed. • If you are loading python3.dll or python36.dll in your own executable, explicitly call or (at least) before. • Clear and/or overwrite and set before launching python.exe from your application. • If you cannot use the previous suggestions (for example, you are a distribution that allows people to run python.exe directly), ensure that the landmark file ( Lib os.py) exists in your install directory.

(Note that it will not be detected inside a ZIP file, but a correctly named ZIP file will be detected instead.) These will ensure that the files in a system-wide installation will not take precedence over the copy of the standard library bundled with your application. Otherwise, your users may experience problems using your application. Note that the first suggestion is the best, as the other may still be susceptible to non-standard paths in the registry and user site-packages. New in version 3.5.

The embedded distribution is a ZIP file containing a minimal Python environment. It is intended for acting as part of another application, rather than being directly accessed by end-users.

When extracted, the embedded distribution is (almost) fully isolated from the user’s system, including environment variables, system registry settings, and installed packages. The standard library is included as pre-compiled and optimized.pyc files in a ZIP, and python3.dll, python36.dll, python.exe and pythonw.exe are all provided. Tcl/tk (including all dependants, such as Idle), pip and the Python documentation are not included. Note The embedded distribution does not include the and it is the responsibility of the application installer to provide this. The runtime may have already been installed on a user’s system previously or automatically via Windows Update, and can be detected by finding ucrtbase.dll in the system directory.

Third-party packages should be installed by the application installer alongside the embedded distribution. Using pip to manage dependencies as for a regular Python installation is not supported with this distribution, though with some care it may be possible to include and use pip for automatic updates. In general, third-party packages should be treated as part of the application (“vendoring”) so that the developer can ensure compatibility with newer versions before providing updates to users. The two recommended use cases for this distribution are described below. Python Application An application written in Python does not necessarily require users to be aware of that fact. The embedded distribution may be used in this case to include a private version of Python in an install package.

Depending on how transparent it should be (or conversely, how professional it should appear), there are two options. Using a specialized executable as a launcher requires some coding, but provides the most transparent experience for users. With a customized launcher, there are no obvious indications that the program is running on Python: icons can be customized, company and version information can be specified, and file associations behave properly.

In most cases, a custom launcher should simply be able to call Py_Main with a hard-coded command line. The simpler approach is to provide a batch file or generated shortcut that directly calls the python.exe or pythonw.exe with the required command-line arguments. In this case, the application will appear to be Python and not its actual name, and users may have trouble distinguishing it from other running Python processes or file associations. With the latter approach, packages should be installed as directories alongside the Python executable to ensure they are available on the path. With the specialized launcher, packages can be located in other locations as there is an opportunity to specify the search path before launching the application. Embedding Python Applications written in native code often require some form of scripting language, and the embedded Python distribution can be used for this purpose. In general, the majority of the application is in native code, and some part will either invoke python.exe or directly use python3.dll. Deadmau5 Get Scraped Zip Media Fire.

For either case, extracting the embedded distribution to a subdirectory of the application installation is sufficient to provide a loadable Python interpreter. As with the application use, packages can be installed to any location as there is an opportunity to specify search paths before initializing the interpreter. Otherwise, there is no fundamental differences between using the embedded distribution and a regular installation.