@janbarsoum You need something called natural sort.
Try this:
import re
def natural_sort(l):
convert = lambda text: int(text) if text.isdigit() else text.lower()
alphanum_key = lambda key: [ convert(c) for c in re.split('([0-9]+)', key) ]
return sorted(l, key = alphanum_key)
OUT = natural_sort(IN[0])
Alternatively, you can use the Natural Sort node from Orchid package