def most_frequent_terms(self, fieldid, number=5, prefix=''):
        
        return nlargest(number, ((tf, token)
                                 for token, _, tf
                                 in self.iter_prefix(fieldid, prefix)))
Returns the top 'number' most frequent terms in the given field as
dataset/ETHPy150Open dokipen/whoosh/src/whoosh/reading.py/IndexReader.most_frequent_terms