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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 prune(self, minimum_word_frequency_percentage=1):
 """ Filter out words that occur less than minimum_word_frequency times. :param minimum_word_frequency_percentage: minimum frequency of words to keep """

        pruned_resulting_documents = []

        for document in self.resulting_documents:
            new_document = []
            for word in document:
                if self.word_in_how_many_documents[word] >= minimum_word_frequency_percentage / 100. * len(
                        self.resulting_documents):
                    new_document.append(word)
            pruned_resulting_documents.append(new_document)
        self.resulting_documents = pruned_resulting_documents