Here are the Python 3 docs for sorting [1], in-place list.sort() [2], and sorted() [3] (which makes a sorted copy of the references). And the Timsort Wikipedia page [4].

[1] https://docs.python.org/3/howto/sorting.html#sort-stability-...

[2] https://docs.python.org/3/library/stdtypes.html#list.sort

[3] https://docs.python.org/3/library/functions.html#sorted

[4] https://en.wikipedia.org/wiki/Timsort