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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 sinogram_as_radon(uSin, align=True):
 r"""Compute the phase from a complex wave field sinogram This step is essential when using the ray approximation before computation of the refractive index with the inverse Radon transform. Parameters uSin: 2d or 3d complex ndarray The background-corrected sinogram of the complex scattered wave :math:`u(\mathbf{r})/u_0(\mathbf{r})`. The first axis iterates through the angles :math:`\phi_0`. align: bool Tries to correct for a phase offset in the phase sinogram. Returns ------- phase: 2d or 3d real ndarray The unwrapped phase array corresponding to `uSin`. See Also -------- skimage.restoration.unwrap_phase: phase unwrapping radontea.backproject_3d: e.g. reconstruction via backprojection """

    ndims = len(uSin.shape)

    if ndims == 2:
        # unwrapping is very important
        phiR = np.unwrap(np.angle(uSin), axis=-1)
    else:
        # Unwrap gets the dimension of the problem from the input
        # data. Since we have a sinogram, we need to pass it the
        # slices one by one.
        phiR = np.angle(uSin)
        for ii in range(len(phiR)):
            phiR[ii] = unwrap_phase(phiR[ii], seed=47)

    if align:
        align_unwrapped(phiR)

    return phiR