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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 analyze(qpi, model, n0, r0, c0=None, imagekw={}, ret_center=False, ret_pha_offset=False, ret_qpi=False):
 """Fit refractive index and radius to a phase image of a sphere Parameters qpi: QPImage Quantitative phase image information model: str Name of the light-scattering model (see :const:`qpsphere.models.available`) n0: float Approximate refractive index of the sphere r0: float Approximate radius of the sphere [m] c0: tuple of (float, float) Approximate center position in ndarray index coordinates [px]; if set to `None` (default), the center of the image is used. imagekw: dict Additional keyword arguments to :func:`qpsphere.imagefit.alg.match_phase`. ret_center: bool Return the center coordinate of the sphere ret_pha_offset: bool If True, return the phase image background offset. ret_qpi: bool If True, return the modeled data as a :class:`qpimage.QPImage`. Returns ------- n: float Computed refractive index r: float Computed radius [m] c: tuple of floats Only returned if `ret_center` is True Center position of the sphere [px] pha_offset: float Only returned if `ret_pha_offset` is True Phase image background offset qpi_sim: qpimage.QPImage Only returned if `ret_qpi` is True Modeled data """

    res = match_phase(qpi, model=model, n0=n0, r0=r0, c0=c0,
                      ret_center=ret_center,
                      ret_pha_offset=ret_pha_offset,
                      ret_qpi=ret_qpi,
                      **imagekw)
    return res