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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 sample_path(self, seed):
 """ Return the model name and a list of branch ids. :param seed: the seed used for the sampling """

        branchset = self.root_branchset
        branch_ids = []
        while branchset is not None:
            [branch] = sample(branchset.branches, 1, seed)
            branch_ids.append(branch.branch_id)
            branchset = branch.child_branchset
        modelname = self.root_branchset.get_branch_by_id(branch_ids[0]).value
        return modelname, branch_ids