code: def test_run_acc_empty(self):
      self.assertEqual(
          model_selection.IIDAccuracySelectionMethod.run_acc(Q([])),
          None,
      )
  
imports: import argparse
  import itertools
  import json
  import os
  import subprocess
  import sys
  import time
  import unittest
  import uuid
  import torch
  from domainbed import model_selection
  from domainbed.lib.query import Q
  from parameterized import parameterized
label_desc: Use image node_id 2 for calling the TestIIDAccuracySelectionMethod obj's underlying member method code with example usage: obj.test_run_acc_empty() without return types