Time In A Bottle

Rules:

Ordinary sudoku rules apply. This puzzle takes place on a klein bottle. The top and bottom of the grid are glued together–they obey periodic boundary conditions. The left and right side are twisted and then glued together. The circles in the grid represent clocks. The four digits surrounding a white clock must strictly increase in a clockwise fashion starting from any of the four cells. The four digits surrounding a black clock must strictly increase in an anti-clockwise fashion starting from any of the four cells. All possible clocks are marked. (Don’t forget that all possible clocks are marked!)

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