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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 delete_branch(self, repo_name, branch_name):
 """ Deletes a branch, but leaves the commits themselves intact. In other words, those commits can still be accessed via commit IDs and other branches they happen to be on. Params: * repo_name: The name of the repo. * branch_name: The name of the branch to delete. """

        res = proto.DeleteBranchRequest(repo=Repo(name=repo_name), branch=branch_name)
        self.stub.DeleteBranch(res, metadata=self.metadata)