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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 most_frequent(self, k):
 """ Returns a vocabulary with the most frequent `k` words. Args: k (integer):
 specifies the top k most frequent words to be returned. """

    word_count = {w:self.word_count[w] for w in self.words[:k]}
    return CountedVocabulary(word_count=word_count)