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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 to_file(self, f):
 """Write vocab to a file. :param (file) f: a file object, e.g. as returned by calling `open` File format: word0<TAB>count0 word1<TAB>count1 """

        for word in self._index2word:
            count = self._counts[word]
            f.write(u'{}\t{}\n'.format(word, count).encode('utf-8'))