Group list of date by time interval Python

Question

[\'2017-07.csv\', \'2017-08.csv\', \'2017-09.csv\', \'2017-10.csv\', \'2017-11.csv\', \'2017-12.csv\', \'2019-01.csv\', \'2019-02.csv\', \'2019-03.csv\', \'2019-04.csv