code: def ccmodmd_relax(k):
      
  
      mp_D_X[k] = mp_drlx * mp_D_X[k] + (1 - mp_drlx) * mp_D_Y0
      mp_DX[k] = mp_drlx * mp_DX[k] + (1 - mp_drlx) * (mp_D_Y1[k] + mp_S[k])
docs: Do relaxation for the ccmod stage. The only parameter is the slice
      index `k` and there are no return values; all inputs and outputs are
      from and to global variables.