.. class:: FileLoader(fullname, path)

An abstract base class which inherits from :class:`ResourceLoader` and

:class:`ExecutionLoader`, providing concreate implementations of

:meth:`ResourceLoader.get_data` and :meth:`ExecutionLoader.get_filename`.

The *fullname* argument is a fully resolved name of the module the loader is

to handle. The *path* argument is the path to the file for the module.

.. versionadded:: 3.3

.. attribute:: name

The name of the module the loader can handle.

.. attribute:: path

Path to the file of the module.

.. method:: get_filename(fullname)

Returns :attr:`path`.

.. method:: get_data(path)

Returns the open, binary file for *path*.

.. class:: FileFinder(path, \*loader_details)

A concrete implementation of :class:`importlib.abc.Finder` which caches

results from the file system.

The *path* argument is the directory for which the finder is in charge of

searching.

The *loader_details* argument is a variable number of 3-item tuples each

containing a loader, file suffixes the loader recognizes, and a boolean

representing whether the loader handles packages.

The finder will cache the directory contents as necessary, making stat calls

for each module search to verify the cache is not outdated. Because cache

staleness relies upon the granularity of the operating system's state

information of the file system, there is a potential race condition of

searching for a module, creating a new file, and then searching for the

module the new file represents. If the operations happen fast enough to fit

within the granularity of stat calls, then the module search will fail. To

prevent this from happening, when you create a module dynamically, make sure

to call :func:`importlib.invalidate_caches`.

.. versionadded:: 3.3

.. attribute:: path

The path the finder will search in.

.. method:: find_module(fullname)

Attempt to find the loader to handle *fullname* within :attr:`path`.

.. method:: invalidate_caches()

Clear out the internal cache.

.. classmethod:: path_hook(\*loader_details)

A class method which returns a closure for use on :attr:`sys.path_hooks`.

An instance of :class:`FileFinder` is returned by the closure using the

path argument given to the closure directly and *loader_details*

indirectly.

If the argument to the closure is not an existing directory,

:exc:`ImportError` is raised.

.. class:: SourceFileLoader(fullname, path)

A concrete implementation of :class:`importlib.abc.SourceLoader` by

subclassing :class:`importlib.abc.FileLoader` and providing some concrete

implementations of other methods.

.. versionadded:: 3.3

.. attribute:: name

The name of the module that this loader will handle.

.. attribute:: path

The path to the source file.

.. method:: is_package(fullname)

Return true if :attr:`path` appears to be for a package.

.. method:: path_stats(path)

Concrete implementation of :meth:`importlib.abc.SourceLoader.path_stats`.

.. method:: set_data(path, data)

Concrete implementation of :meth:`importlib.abc.SourceLoader.set_data`.

.. method:: load_module(fullname)

Load the specified module if it is the same as :attr:`name`.

.. class:: _SourcelessFileLoader(fullname, path)

A concrete implementation of :class:`importlib.abc.FileLoader` which can

import bytecode files (i.e. no source code files exist).

It is **strongly** suggested you do not rely on this loader (hence the

leading underscore of the class). Direct use of bytecode files (and thus not

source code files) inhibits your modules from being usable by all Python

implementations. It also runs the risk of your bytecode files not being

usable by new versions of Python which change the bytecode format. This

class is only documented as it is directly used by import and thus can

potentially have instances show up as a module's ``__loader__`` attribute.

.. versionadded:: 3.3

.. attribute:: name

The name of the module the loader will handle.

.. attribute:: path

The path to the bytecode file.

.. method:: is_package(fullname)

Determines if the module is a package based on :attr:`path`.

.. method:: get_code(fullname)

Returns the code object for :attr:`name` created from :attr:`path`.

.. method:: get_source(fullname)

Returns ``None`` as bytecode files have no source when this loader is

used.

.. method:: load_module(fullname)

Loads the specified module if it is the same as :attr:`name`.

.. class:: ExtensionFileLoader(fullname, path)

A concrete implementation of :class:`importlib.abc.InspectLoader` for

extension modules.

The *fullname* argument specifies the name of the module the loader is to

support. The *path* argument is the path to the extension module's file.

.. versionadded:: 3.3

.. attribute:: name

Name of the module the loader supports.

.. attribute:: path

Path to the extension module.

.. method:: load_module(fullname)

Loads the extension module if and only if *fullname** is the same as

:attr:`name`.

.. method:: is_package(fullname)

Returns ``False`` as extension modules can never be packages.

.. method:: get_code(fullname)

Returns ``None`` as extension modules lack a code object.

.. method:: get_source(fullname)

Returns ``None`` as extension modules do not have source code.