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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 get_skeleton(self):
 """ Return an empty copy of the source model, i.e. without sources, but with the proper attributes for each SourceGroup contained within. """

        src_groups = []
        for grp in self.src_groups:
            sg = copy.copy(grp)
            sg.sources = []
            src_groups.append(sg)
        return self.__class__(self.names, self.weight, self.path, src_groups,
                              self.num_gsim_paths, self.ordinal, self.samples)