The builtin module itertools contains plenty of functions to work with lists and iterators. Most functions in this module return iterators themselves, so they can be consumed by loops or next(). You can also convert them to a list.
Below you find a few examples:
.. literalinclude:: example_itertools.py
.. seealso::
`Documentation of the itertools module <https://docs.python.org/3/library/itertools.html>`__