code: def remove_non_latin(input_string, also_keep=None):
      
      if also_keep:
          also_keep += [' ']
      else:
          also_keep = [' ']
      latin_chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
      latin_chars += latin_chars.lower()
      latin_chars += ''.join(also_keep)
      no_latin = "".join([char for char in input_string if char in latin_chars])
      return no_latin
docs: Remove non-Latin characters.
      `also_keep` should be a list which will add chars (e.g. punctuation)
      that will not be filtered.