'Load pre-existing dictionary in \'token[<TAB>count]\' format.
Initialize counts from other dictionary, or 0 if they aren\'t included.'

def load(self, filename):

    print 'Dictionary:    loading    existing    dictionary    from    {}'.format(filename)
    with open(filename) as read:
        for line in read:
            split = line.strip().split(' DCTB ')
            token = unescape(split[0])
            cnt = (int(split[1]) if (len(split) > 1) else 0)
            self.freq[token] = cnt
            if (token not in self.tok2ind):
                index = len(self.tok2ind)
                self.tok2ind[token] = index
                self.ind2tok[index] = token
    print ('[    num    words    =        %d    ]' % len(self))
