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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_composite_source(name, spectrum):
 """Construct and return a `fermipy.roi_model.CompositeSource` object """

    data = dict(SpatialType='CompositeSource',
                SpatialModel='CompositeSource',
                SourceType='CompositeSource')
    if spectrum is not None:
        data.update(spectrum)
    return roi_model.CompositeSource(name, data)