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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 add(self, start, end):
 """ Add the start and end offsets of a matching read. @param start: The C{int} start offset of the read match in the subject. @param end: The C{int} end offset of the read match in the subject. This is Python-style: the end offset is not included in the match. """

        assert start <= end
        self._intervals.append((start, end))