Natural sorting of file names

>>> tables
['wm_raw_draw_data_11.sql', 'wm_similarity.sql', 'wm_renderings.sql', 'wm_raw_draw_data_6.sql', 'wm_raw_draw_data_1.sql', 'wm_raw_draw_data_14.sql', 'wm_raw_draw_data_15.sql', 'wm_raw_draw_data_5.sql', 'wm_raw_draw_data_12.sql', 'wm_raw_draw_data_10.sql', 'wm_raw_draw_data_9.sql', 'wm_raw_draw_data_3.sql', 'wm_challenges.sql', 'wm_votes.sql', 'wm_raw_draw_data_13.sql', 'wm_raw_draw_data_4.sql', 'wm_workers.sql', 'wm_languages.sql', 'wm_formula2challenge.sql', 'wm_raw_draw_data_8.sql', 'wm_raw_draw_data_16.sql', 'wm_raw_draw_data_7.sql', 'wm_formula_svg_missing.sql', 'wm_raw_data2formula.sql', 'wm_raw_draw_data_2.sql', 'wm_invalid_formula_requests.sql', 'wm_raw_draw_data_17.sql', 'wm_user_unknown_formula.sql', 'wm_formula.sql', 'wm_users.sql.gz', 'wm_worker_answers.sql.gz']

>>> import natsort
>>> natsort.natsorted(tables)
['wm_challenges.sql', 'wm_formula2challenge.sql', 'wm_formula.sql', 'wm_formula_svg_missing.sql', 'wm_invalid_formula_requests.sql', 'wm_languages.sql', 'wm_raw_data2formula.sql', 'wm_raw_draw_data_1.sql', 'wm_raw_draw_data_2.sql', 'wm_raw_draw_data_3.sql', 'wm_raw_draw_data_4.sql', 'wm_raw_draw_data_5.sql', 'wm_raw_draw_data_6.sql', 'wm_raw_draw_data_7.sql', 'wm_raw_draw_data_8.sql', 'wm_raw_draw_data_9.sql', 'wm_raw_draw_data_10.sql', 'wm_raw_draw_data_11.sql', 'wm_raw_draw_data_12.sql', 'wm_raw_draw_data_13.sql', 'wm_raw_draw_data_14.sql', 'wm_raw_draw_data_15.sql', 'wm_raw_draw_data_16.sql', 'wm_raw_draw_data_17.sql', 'wm_renderings.sql', 'wm_similarity.sql', 'wm_user_unknown_formula.sql', 'wm_users.sql.gz', 'wm_votes.sql', 'wm_worker_answers.sql.gz', 'wm_workers.sql']