Log Message:
py-more-itertools: update to 8.1.0.

8.1.0
-----

* Bug fixes
    * :func:`partition` works with ``pred=None`` again. (thanks to MSeifert04)

* New itertools
    * :func:`sample` (thanks to tommyod)
    * :func:`nth_or_last` (thanks to d-ryzhikov)

* Changes to existing itertools:
    * The implementation for :func:`divide` was improved. (thanks to jferard)