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import and importlib notes
Alex Willmer edited this page 2024-08-29 09:34:34 +01:00
class module:
__name__ # Full qualified name. Required.
__loader__ # Loader object used to load the module. Required. Deprecated.
__package__ # If the module is a package, same as __name__.
# Otherwise name of parent package, or empty string for
# top-level module. Optional.
__spec__ # ModuleSpec object. Required (except sometimes for __main__).
__path__ # Search path for modules inside package. Required iif a package.
# Presence of __path__ indicates a package.
# Iterable type other than list indicates a namespace package (PEP 420)
__file__ # Path of the file (if any) the module was loaded from. Optional.
__cached__ # Path of cached bytecode (if any) for the module. Optional.
class importlib._bootstrap.BuiltinImporter
def is_package(cls, fullname) -> False:
"built-in modules are never packages."
class importlib.abc.MetaPathFinder:
def find_spec(fullname, path, target=None)
Should return None if this finder can't handle the module.
Raise ModuleNotFoundError to halt any further search for the module.
def invalidate_caches() # Optional
class importlib.abc.Loader:
def create_module(spec)
Return a created module object, or None if the spec should create it.
Raise ImportError if anything prevents creation of the module object.
def exec_module(spec)
Execute the module. Don't return anything.
class importlib.abc.PathEntryFinder:
def find_spec(fullname, target=None)
def invalidate_caches() # Optional
importlib.machinery.ModuleSpec: # Python 3.4+
name # __name__
loader # __loader__
origin # __file__
# None has been seen in the wild (#1042),
# it may indicate a namespace package.
submodule_search_locations
# __path__
# None indicates a non-package.
# List (even empty) indicates a package.
# A custom iterable indicates a namespace package.
loader_state
cached # __cached__
parent # __package__
# Same as name, if the module is a package.
# Otherwise name of parent package,
# or empty string if a top-level module.
has_location # True if origin refers to a loadable location
importlib.find_loader(name, path=None) # Python 3.3-3.11
importlib.util._find_spec(name, path, target=None)
importlib.util.find_spec(name, package=None) # Python 3.4+
importlib.util.spec_from_file_location(nmae, location=None, * loader=None,
submodule_search_locations=...)
_imp module is implemented in https://github.com/python/cpython/blob/3.11/Python/import.c
imp.find_module -> (Optional[fobj], Optional[path], (suffix, mode, type_)) # Python 2.x - 3.11
import.new_module() |
types.ModuleType() |
|
|---|---|---|
| Python 2.x | bytes or unicode |
bytes |
| Python 3.x | unicode |
unicode |
ansible_mitogen.module_finder.Module:
name Unqualified name of the module.
path Filesystem path of the module.
kind One of the constants in `imp`, as returned in `imp.find_module()`
parent `ansible_mitogen.module_finder.Module` of parent package (if any).
pkgutil.ModuleInfo(module_finder, name, ispkg) # namedtuple, Python 3.6+
pkgutil.find_loader(full_name) # Deprecated 3.12, removal 3.14
pkgutil.get_importer(path_item)
pkgutil.get_loader(module_or_name) # Deprecated 3.12, removal 3.14
sys.builtin_module_names: tuple # Python 2.2+, atleast
sys.stdlib_module_names: frozenset # Python 3.10, includes platform specific
# even if not correct platform
https://pypi.org/project/stdlibs/
Module name must be a valid Python identifier
Python 2: r'[A-Za-z_][A-Za-z0-9_]*'
Python 3: https://docs.python.org/3/reference/lexical_analysis.html#identifiers
Python 2.7:
sys.meta_path == []
sys.path_hooks == [<type 'zipimport.zipimporter'>]
Python 3.11:
sys.meta_path == [
<_distutils_hack.DistutilsMetaFinder object at 0x100874e90>,
<class '_frozen_importlib.BuiltinImporter'>,
<class '_frozen_importlib.FrozenImporter'>,
<class '_frozen_importlib_external.PathFinder'>,
]
sys.path_hooks == [
<class 'zipimport.zipimporter'>,
<function FileFinder.path_hook.<locals>.path_hook_for_FileFinder at 0x1007e8900>.
]
Sources
- https://docs.python.org/3/library/importlib.html
- https://peps.python.org/pep-0273/ Import from Zip Archives
- https://peps.python.org/pep-0302/ Import hooks (sys.meta_path, sys.path_hooks)
- https://peps.python.org/pep-0451/ ModuleSpec for import hooks
Issues