code: def test_evaluating():
      a = nn.Linear(1, 1)
      b = nn.Linear(1, 1)
      assert a.training
      assert b.training
      with pfrl.utils.evaluating(a):
          assert not a.training
          assert b.training
          with pfrl.utils.evaluating(b):
              assert not a.training
              assert not b.training
          assert not a.training
          assert b.training
      assert a.training
      assert b.training
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_evaluating() without return types