code: def make_composite_source(name, spectrum):
      
      data = dict(SpatialType='CompositeSource',
                  SpatialModel='CompositeSource',
                  SourceType='CompositeSource')
      if spectrum is not None:
          data.update(spectrum)
      return roi_model.CompositeSource(name, data)
docs: Construct and return a `fermipy.roi_model.CompositeSource` object