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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 items_to_extract(self, offset=0, length=None):
 """ Return an iterable of specific items to extract. As a side-effect, set self.items_to_extract_length. :param offset: where to start extracting :param length: how many to extract :return: An iterable of the specific """

        endoffset = length and offset + length
        qs = self.origin_data()[offset:endoffset]
        self.items_to_extract_length = qs.count()
        return qs