/Doc/library/pkgutil.rst
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- :mod:`pkgutil` --- Package extension utility
- ============================================
- .. module:: pkgutil
- :synopsis: Utilities to support extension of packages.
- .. versionadded:: 2.3
- This module provides functions to manipulate packages:
- .. function:: extend_path(path, name)
- Extend the search path for the modules which comprise a package. Intended use is
- to place the following code in a package's :file:`__init__.py`::
- from pkgutil import extend_path
- __path__ = extend_path(__path__, __name__)
- This will add to the package's ``__path__`` all subdirectories of directories on
- ``sys.path`` named after the package. This is useful if one wants to distribute
- different parts of a single logical package as multiple directories.
- It also looks for :file:`\*.pkg` files beginning where ``*`` matches the *name*
- argument. This feature is similar to :file:`\*.pth` files (see the :mod:`site`
- module for more information), except that it doesn't special-case lines starting
- with ``import``. A :file:`\*.pkg` file is trusted at face value: apart from
- checking for duplicates, all entries found in a :file:`\*.pkg` file are added to
- the path, regardless of whether they exist on the filesystem. (This is a
- feature.)
- If the input path is not a list (as is the case for frozen packages) it is
- returned unchanged. The input path is not modified; an extended copy is
- returned. Items are only appended to the copy at the end.
- It is assumed that ``sys.path`` is a sequence. Items of ``sys.path`` that are
- not (Unicode or 8-bit) strings referring to existing directories are ignored.
- Unicode items on ``sys.path`` that cause errors when used as filenames may cause
- this function to raise an exception (in line with :func:`os.path.isdir`
- behavior).
- .. function:: get_data(package, resource)
- Get a resource from a package.
- This is a wrapper for the PEP 302 loader :func:`get_data` API. The package
- argument should be the name of a package, in standard module format
- (foo.bar). The resource argument should be in the form of a relative
- filename, using ``/`` as the path separator. The parent directory name
- ``..`` is not allowed, and nor is a rooted name (starting with a ``/``).
- The function returns a binary string that is the contents of the
- specified resource.
- For packages located in the filesystem, which have already been imported,
- this is the rough equivalent of::
- d = os.path.dirname(sys.modules[package].__file__)
- data = open(os.path.join(d, resource), 'rb').read()
- If the package cannot be located or loaded, or it uses a PEP 302 loader
- which does not support :func:`get_data`, then None is returned.