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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 merge(intervals):
 """ Merge two intervals into one. """

        out = []
        for i in sorted(intervals, key=lambda i: i.start):
            if out and i.start <= out[-1].end:
                out[-1].end = max(out[-1].end, i.end)
            else:
                out += i,
        return out