bpo-31799: Make module.__spec__ more discoverable (#4010)
bpo-31799: Make module.__spec__ more discoverable
diff --git a/Doc/library/importlib.rst b/Doc/library/importlib.rst
index 3a72648..3d350e8 100644
--- a/Doc/library/importlib.rst
+++ b/Doc/library/importlib.rst
@@ -1048,7 +1048,15 @@
.. class:: ModuleSpec(name, loader, *, origin=None, loader_state=None, is_package=None)
- A specification for a module's import-system-related state.
+ A specification for a module's import-system-related state. This is
+ typically exposed as the module's ``__spec__`` attribute. In the
+ descriptions below, the names in parentheses give the corresponding
+ attribute available directly on the module object.
+ E.g. ``module.__spec__.origin == module.__file__``. Note however that
+ while the *values* are usually equivalent, they can differ since there is
+ no synchronization between the two objects. Thus it is possible to update
+ the module's ``__path__`` at runtime, and this will not be automatically
+ reflected in ``__spec__.submodule_search_locations``.
.. versionadded:: 3.4