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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _word_to_score(self, ids, scores):
 """Return a map from each word to its score. :param (np.array) ids: a vector of word ids :param (np.array) scores: a vector of scores :return (dict[unicode, float]):
 a map from each word (unicode) to its score (float) """

        # should be 1-D vectors
        assert len(ids.shape) == 1
        assert ids.shape == scores.shape

        w2s = {}
        for i in range(len(ids)):
            w2s[self.vocab.index2word(ids[i])] = scores[i]
        return w2s