old_contents: def alphanum_sort(string):
      char_string = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0246813579"
      return ''.join(sorted(string, key=char_string.index))
  
  print(alphanum_sort("Sorting0123456789"))             # ginortS0246813579
  print(alphanum_sort("foobar1237348421"))              # abfoor2244811337
  print(alphanum_sort("789765445whjdbjwhwfbs977865"))   # bbdfhhjjswww446688555777799
  
new_contents: def alphanum_sort(alphanum_string):
      char_string = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0246813579"
      return ''.join(sorted(alphanum_string, key=char_string.index))
  
  print(alphanum_sort("Sorting0123456789"))             # ginortS0246813579
  print(alphanum_sort("foobar1237348421"))              # abfoor2244811337
  print(alphanum_sort("789765445whjdbjwhwfbs977865"))   # bbdfhhjjswww446688555777799
  
subject: Rename argument