How to use the ruptures.utils.Bnode function in ruptures

if bkp % self.jump == 0:
                    if bkp - start >= self.min_size and end - bkp >= self.min_size:
                        bkps.append(bkp)
            if len(bkps) > 0:  # at least one admissible breakpoint was found
                bkp = min(bkps, key=lambda x: abs(x - mid))
                partition.remove((start, end))
                partition.append((start, bkp))
                partition.append((bkp, end))
                stop = False

        partition.sort()
        # compute segment costs
        leaves = list()
        for start, end in partition:
            val = self.cost.error(start, end)
            leaf = Bnode(start, end, val)
            leaves.append(leaf)
        return leaves

def _merge(self, left, right):
        """Merge two contiguous segments."""
        assert left.end == right.start, "Segments are not contiguous."
        start, end = left.start, right.end
        val = self.cost.error(start, end)
        node = Bnode(start, end, val, left=left, right=right)
        return node