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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 xdifference(self, to):
 """ Generator Gives the difference of quadkeys between self and to Generator in case done on a low level Only works with quadkeys of same level """

        x,y = 0,1
        assert self.level == to.level
        self_tile = list(self.to_tile()[0])
        to_tile = list(to.to_tile()[0])
        if self_tile[x] >= to_tile[x] and self_tile[y] <= self_tile[y]:
            ne_tile, sw_tile = self_tile, to_tile
        else:
            sw_tile, ne_tile = self_tile, to_tile
        cur = ne_tile[:]
        while cur[x] >= sw_tile[x]:
            while cur[y] <= sw_tile[y]:
                yield from_tile(tuple(cur), self.level)
                cur[y] += 1
            cur[x] -= 1
            cur[y] = ne_tile[y]