The term `Immutable` in the `sequence` entry of the glossary is used incorrectly, in fact dicts accepts hashable keys, which is not the same as immutable.
:class:`tuple`, and :class:`bytes`. Note that :class:`dict` also
supports :meth:`~object.__getitem__` and :meth:`!__len__`, but is considered a
mapping rather than a sequence because the lookups use arbitrary
- :term:`immutable` keys rather than integers.
+ :term:`hashable` keys rather than integers.
The :class:`collections.abc.Sequence` abstract base class
defines a much richer interface that goes beyond just