docs: def delete(self):
          """Delete a running cluster."""
          stacks = [
              self.utilities_name,
              self.spot_nodes_name,
              self.node_group_name,
              self.cluster_name,
              self.vpc_name,
              self.role_name
          ]
          # Execute creation.
          for stack in tqdm.tqdm(stacks, ncols=70):
              self.delete_stack(stack)