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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 cell_sides(self):
 """Side lengths of all 'inner' cells of a uniform partition. Only defined if ``self.grid`` is uniform. Examples -------- We create a partition of the rectangle [0, 1] x [-1, 2] into 3 x 3 cells, where the grid points lie on the boundary. This means that the grid points are [0, 0.5, 1] x [-1, 0.5, 2], i.e. the inner cell has side lengths 0.5 x 1.5: array([ 0.5, 1.5]) """

        sides = self.grid.stride
        sides[sides == 0] = self.extent[sides == 0]
        return sides