Calculate the vocabulary.

def vocab_counter(args):
  """Calculate the vocabulary."""
  if isinstance(args.input, TextFiles):
    v = CountedVocabulary.from_textfiles(args.input, workers=args.workers)
  else:
    v = CountedVocabulary.from_textfile(args.input, workers=args.workers)
  if args.min_count > 1: 
    v = v.min_count(args.min_count)
  if args.most_freq > 0:
    v = v.most_frequent(args.most_freq)
  print(v)