Co-authored-by: Cameron Beck <94604154+cbkinase@users.noreply.github.com>
:func:`itertools.groupby`.
There are several ways to create a key function. For example. the
- :meth:`str.lower` method can serve as a key function for case insensitive
+ :meth:`str.casefold` method can serve as a key function for case insensitive
sorts. Alternatively, a key function can be built from a
:keyword:`lambda` expression such as ``lambda r: (r[0], r[2])``. Also,
:func:`operator.attrgetter`, :func:`operator.itemgetter`, and