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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 cbpdn_setdict():
 """Set the dictionary for the cbpdn stage. There are no parameters or return values because all inputs and outputs are from and to global variables. """


    global mp_DSf
    # Set working dictionary for cbpdn step and compute DFT of dictionary
    # D and of D^T S
    mp_Df[:] = sl.rfftn(mp_D_Y, mp_cri.Nv, mp_cri.axisN)
    if mp_cri.Cd == 1:
        mp_DSf[:] = np.conj(mp_Df) * mp_Sf
    else:
        mp_DSf[:] = sl.inner(np.conj(mp_Df[np.newaxis, ...]), mp_Sf,
                              axis=mp_cri.axisC+1)