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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 unpack(self, format_text):
 """Unpack bytes using struct modules format :param format_text: struct's module format :type format_text: :class:`str` :return data: result from :func:`struct.unpack_from` :rtype: :class:`tuple` """

        data = _unpack_from(format_text, self.data, self.offset)
        self.offset += _calcsize(format_text)
        return data