code: def test_adjointlayout_triple(self):
      layout = self.view3 << self.view2 << self.view1
      self.assertEqual(layout.main, self.view3)
      self.assertEqual(layout.right, self.view2)
      self.assertEqual(layout.top, self.view1)
  
imports: import numpy
  import pytest
  from holoviews import AdjointLayout, Element, GridSpace, HoloMap, Layout, NdLayout, Overlay
  from holoviews.element import Curve, HLine, Image
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 3 for calling the AdjointLayoutTest obj's underlying member method code with example usage: obj.test_adjointlayout_triple() without return types