'Tags the sequence with the highest probability state sequence. This
uses the best_path method to find the Viterbi path.
:return: a labelled sequence of symbols
:rtype: list
:param unlabeled_sequence: the sequence of unlabeled symbols
:type unlabeled_sequence: list'

def tag(self, unlabeled_sequence):

    unlabeled_sequence = self._transform(unlabeled_sequence)
    return self._tag(unlabeled_sequence)
