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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 _from_arrays(self, x, y, z):
 """ Create VTK rectilinear grid directly from numpy arrays. Each array gives the uniques coordinates of the mesh along each axial direction. To help ensure you are using this correctly, we take the unique values of each argument. Parameters x : np.ndarray Coordinates of the nodes in x direction. y : np.ndarray Coordinates of the nodes in y direction. z : np.ndarray Coordinates of the nodes in z direction. """

        x = np.unique(x.ravel())
        y = np.unique(y.ravel())
        z = np.unique(z.ravel())
        # Set the cell spacings and dimensions of the grid
        self.SetDimensions(len(x), len(y), len(z))
        self.SetXCoordinates(numpy_to_vtk(x))
        self.SetYCoordinates(numpy_to_vtk(y))
        self.SetZCoordinates(numpy_to_vtk(z))