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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 __pair_repack(self, f, plist):
 """ Flattens a sequence of pairs to pass through `f`, and then re-pairs the result. Parameters f : callable A function that accepts a sequence and returns a sequence plist: A sequence of pairs Returns ------- qlist : sequence Equivalent to (tuple(f(p)) for p in plist) """

        ulist = f(u for p in plist for u in p)
        for u in ulist:
            v = next(ulist)
            yield u, v