that are not text encodings (multiple issues).
* :ref:`A ModuleSpec Type <whatsnew-pep-451>` for the Import System
(:pep:`451`). (Affects importer authors.)
+* The :mod:`marshal` format has been made :ref:`more compact and efficient
+ <whatsnew-marshal-3>` (:issue:`16475`).
New library modules:
(:class:`~email.contentmanager.EmailMessage`) that :ref:`simplify MIME
handling <whatsnew_email_contentmanager>` (:issue:`18891`).
* The :mod:`inspect` and :mod:`pydoc` modules are now capable of
- correct introspection of a much wider variety of callable objects
+ correct introspection of a much wider variety of callable objects,
+ which improves the output of the Python :func:`help` system.
* The :mod:`ipaddress` module API has been declared stable
Security improvements:
* Leveraging :pep:`442`, :ref:`module globals are no longer set to None
during finalization <whatsnew-pep-442>`, in most cases (:issue:`18214`).
* :ref:`Configurable memory allocators <whatsnew-pep-445>` (:pep:`445`).
-* :ref:`Secure and interchangeable hash algorithm <whatsnew-pep-456>`
- (:pep:`456`).
* :ref:`Argument Clinic <whatsnew-pep-436>` (:pep:`436`).
-* The :mod:`marshal` format has been made :ref:`more compact and efficient
- <whatsnew-marshal-3>` (:issue:`16475`).
Please read on for a comprehensive list of user-facing changes, including many
other smaller improvements, CPython optimizations, deprecations, and potential