code: def test_getitem(self):
      assert self.av[0] is self.s[0]
      assert self.av[4] is self.p[4]
      assert self.av[2]["color"] == 1
      pytest.raises(KeyError, self.av[2].__getitem__, "watch")
      pytest.raises(KeyError, self.av.__getitem__, 8)
  
imports: import pickle
  import pytest
  import networkx
label_desc: Use image node_id 5 for calling the TestUnionAtlas obj's underlying member method code with example usage: obj.test_getitem() without return types