test_natural_sort.py

import re

def _atoi(text):
    return int(text) if text.isdigit() else text

def natural_sort(text):
    return [_atoi(a) for a in re.split(r'(\d+)', text)]


lst = ['mxene_001g', 'mxene_002', 'mxene_003', 'mxene_004', 'mxene_005', 'opls_753', 'opls_754', 'opls_755', 'opls_759']

sorted_lst = lst 
sorted_lst.sort(key=natural_sort)

assert lst == sorted_lst