---
name: "dh_python2"
section: "1"
platform: "linux"
package: "dh-python"
version: "4.20201102+nmu1"
release: "Debian 11 (Bullseye)"
platforms: ["linux"]
url: "https://new.carta.tech/dh_python2"
---

# dh\_python2(1)

calculates Python dependencies, adds maintainer scripts to byte compile files, etc.

## NAME

dh\_python2 - calculates Python dependencies, adds maintainer scripts to byte compile files, etc.

## SYNOPSIS

dh\_python2 -p PACKAGE \[-V \[X.Y\]\[-\]\[A.B\]\] DIR\_OR\_FILE \[-X REGEXPR\]

## DESCRIPTION

### QUICK GUIDE FOR MAINTAINERS

- •

  if necessary, describe supported Python versions via X-Python-Version field in debian/control,

- •

  build depend on dh-python

- •

  build-depend on python or python-all or python-all-dev (\>= 2.6.6-3~),

- •

  build module/application using its standard build system, remember to build extensions for all supported Python versions (loop over **pyversions -vr**),

- •

  install files to the *standard* locations, add *--install-layout=deb* to setup.py's install command if your package is using distutils,

- •

  add *python2* to dh's --with option, or:

- •

  *include /usr/share/cdbs/1/class/python-distutils.mk* in debian/rules and depend on *cdbs (\>= 0.4.90)*, or:

- •

  call **dh\_python2** in the *binary-\** target,

- •

  add *${python:Depends}* to Depends

### NOTES

In order to support more than one Python version in the same binary package, dh\_python2 (unlike dh\_pycentral and dh\_pysupport) creates symlinks to all supported Python versions at build time. It means binNMU (or sourceful upload in case of architecture independent packages) is required once a list of supported Python version is changed. It's faster and more robust than its competitors, though.

### dependencies

dh\_python2 tries to translate Python dependencies from the *requires.txt* file to Debian dependencies. In many cases, this works without any additional configuration because dh\_python2 comes with a build-in mapping of Python module names to Debian packages that is periodically regenerated from the Debian archive. By default, the version information in the Python dependencies is discarded. If you want dh\_python2 to generate more strict dependencies (e.g. to avoid ABI problems), or if the automatic mapping does not work correctly for your package, you have to provide dh\_python2 with additional rules for the translation of Python module to Debian package dependencies.

For a package *python-foo* that depends on a package *python-bar*, there are two files that may provide such rules:

- 1\.

  If the *python-foo* source package ships with a *debian/pydist-overrides* file, this file is used by dh\_python during the build of *python-foo*.

- 2\.

  If the *python-bar* source package ships with a *debian/python-bar.pydist* file (and uses dh\_python), this file will be included in the binary package as */usr/share/dh-python/dist/cpython2/python-bar*. During the build of *python-foo*, dh\_python will then find and use the file.

Both files have the same format described in */usr/share/doc/dh-python/README.PyDist*. If all you want is to generate versioned dependencies (and assuming that the *python-bar* package provides the *pybar* Python module), in most cases it will be sufficient to put the line **pybar python-bar; PEP386** into either of the above files.

### namespace feature

dh\_python2 parses Egg's namespace\_packages.txt files (in addition to --namespace command line argument(s)) and drops empty \_\_init\_\_.py files from binary package. pycompile will regenerate them at install time and pyclean will remove them at uninstall time (if they're no longer used in installed packages). It's still a good idea to provide \_\_init\_\_.py file in one of binary packages (even if all other packages use this feature).

### private dirs

*/usr/share/foo*, */usr/share/games/foo*, */usr/lib/foo* and */usr/lib/games/foo* private directories are scanned for Python files by default (where *foo* is binary package name). If your package ships Python files in some other directory, add another dh\_python2 call in debian/rules with directory name as an argument - you can use different set of options in this call. If you need to change options (f.e. a list of supported Python versions) for a private directory that is checked by default, invoke dh\_python2 with --skip-private option and add another call with a path to this directory and new options.

### debug packages

In binary packages which name ends with *-dbg*, all files in */usr/lib/python2.X/{site,dist}-packages/* directory that have extensions different than *so* or *h* are removed by default. Use --no-dbg-cleaning option to disable this feature.

### pyinstall files

Files listed in debian/pkg.pyinstall file will be installed as public modules (i.e. into .../dist-packages/ directory) for all requested Python versions (dh\_install doesn't know about python's site- vs. dist-packages issue).

Syntax: **path/to/file \[VERSION\_RANGE\] \[NAMESPACE\]**

debian directory is automatically removed from the path, so you can place your files in debian/ directory and install them from this location (if you want to install them in "debian" namespace, set NAMESPACE to debian). If NAMESPACE is set, all listed files will be installed in .../dist-packages/NAMESPACE/ directory.

- **Examples:**

  - •

    **foo.py** installs .../dist-packages/foo.py for all supported Python versions

  - •

    **foo/bar.py 2.6-** installs .../dist-packages/foo/bar.py for versions \>= 2.6

  - •

    **foo/bar.py spam** installs .../dist-packages/spam/bar.py

  - •

    **debian/\*.py spam.egg 2.5** installs .../python2.5/site-packages/spam/egg/\*.py files

### pyremove files

If you want to remove some public modules (i.e. files in .../dist-packages/ directory) installed by build system (from all supported Python versions or only from a subset of these versions), add them to debian/pkg.pyremove file.

- **Examples:**

  - •

    **\*.pth** removes .pth files from .../dist-packages/

  - •

    **bar/baz.py 2.5** removes .../python2.5/site-packages/bar/baz.py

### overriding supported / default Python versions

If you want to override system's list of supported Python versions or the default one (f.e. to build a package that includes symlinks for older version of Python or compile .py files only for given interpreter version), you can do that via *DEBPYTHON\_SUPPORTED* and/or *DEBPYTHON\_DEFAULT* env. variables.

Example: **2.5,2.7** limits the list of supported Python versions to Python 2.5 and Python 2.7.

## OPTIONS

- **--version**

  show program's version number and exit

- **-h, --help**

  show help message and exit

- **--no-guessing-versions**

  disable guessing other supported Python versions

- **--no-guessing-deps**

  disable guessing dependencies

- **--no-dbg-cleaning**

  do not remove any files from debug packages

\--no-ext-rename do not add magic tags nor multiarch tuples to extension file names

- **--no-shebang-rewrite**

  do not rewrite shebangs

- **--skip-private**

  don't check private directories

- **-v, --verbose**

  turn verbose mode on

- **-i, --indep**

  act on architecture independent packages

- **-a, --arch**

  act on architecture dependent packages

- **-q, --quiet**

  be quiet

- **-p** *PACKAGE,* **--package=***PACKAGE*

  act on the package named PACKAGE

- **-N** *NO\_PACKAGE,* **--no-package=***NO\_PACKAGE*

  do not act on the specified package

- **-V** *VRANGE*

  specify list of supported Python versions. See [pycompile(1)](/pycompile/1.md) for examples

- **-X** *REGEXPR,* **--exclude=***REGEXPR*

  exclude items that match given REGEXPR. You may use this option multiple times to build up a list of things to exclude.

- **--compile-all**

  compile all files from given private directory in postinst/rtupdate not just the ones provided by the package (i.e. do not pass the --package parameter to pycompile/pyclean)

- **--accept-upstream-versions**

  accept upstream versions while translating Python dependencies into Debian ones

- **--depends=***DEPENDS*

  translate given requirements into Debian dependencies and add them to ${python:Depends}. Use it for missing items in requires.txt

- **--depends-section=***SECTION*

  translate requirements from given sections of requres.txt file into Debian dependencies and add them to ${python:Depends}.

- **--recommends=***RECOMMENDS*

  translate given requirements into Debian dependencies and add them to ${python:Recommends}

- **--recommends-section=***SECTION*

  translate requirements from given sections of requres.txt file into Debian dependencies and add them to ${python:Recommends}.

- **--suggests=***SUGGESTS*

  translate given requirements into Debian dependencies and add them to ${python:Suggests}

- **--suggests-section=***SECTION*

  translate requirements from given sections of requres.txt file into Debian dependencies and add them to ${python:Suggests}.

- **--requires=***FILENAME*

  translate requirements from given file(s) into Debian dependencies and add them to ${python:Depends}

- **--namespace=***NAME*

  use this option (multiple time if necessary) if namespace\_packages.txt is not complete

- **--ignore-namespace**

  ignore Egg's namespace declaration and --namespace option. This option will disable removing (and recreating at install time) empty \_\_init\_\_.py files. Removing namespace\_packages.txt from egg-info directory has the same effect.

- **--clean-pycentral**

  generate maintainer script that will remove byte code generated by python-central helper

- **--shebang=***COMMAND*

  use given command as shebang in scripts

- **--ignore-shebangs**

  do not translate shebangs into Debian dependencies

## SEE ALSO

- •

  /usr/share/doc/python/python-policy.txt.gz

- •

  /usr/share/doc/dh-python/README.PyDist

- •

  [pybuild(1)](/pybuild/1.md)

- •

  [pycompile(1)](/pycompile/1.md), [pyclean(1)](/pyclean/1.md)

- •

  [dh\_python3(1)](/dh_python3/1.md), [py3compile(1)](/py3compile/1.md), [py3clean(1)](/py3clean/1.md)

- •

  Wiki page about converting package to dh\_python2: *http://wiki.debian.org/Python/TransitionToDHPython2*

- •

  *http://deb.li/dhp2* - most recent version of this document

## AUTHOR

Piotr Ożarowski, 2012-2013