def METHOD_NAME(self):
    """
    @brief    Generate all the cells in the mesh
    @return   cell : ndarray, shape (NC, 2), contains node indices of each cell
    """
    NC = self.NC
    METHOD_NAME = np.zeros((NC, 2), dtype=self.itype)
    METHOD_NAME[:, 0] = range(0, NC)
    METHOD_NAME[:, 1] = range(1, NC+1) 
    return METHOD_NAME