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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 make_mapcube_source(name, Spatial_Filename, spectrum):
 """Construct and return a `fermipy.roi_model.MapCubeSource` object """

    data = dict(Spatial_Filename=Spatial_Filename)
    if spectrum is not None:
        data.update(spectrum)

    return roi_model.MapCubeSource(name, data)