class_docstr: For testing of AttrTree
class_docstr_tok: ["For","testing","of","AttrTree"]
code: def test_delitem_on_node(self):
      del self.tree.B["II"]
      self.assertNotEqual(self.tree.B.II, 2)
      self.assertNotIn(("B", "II"), self.tree.data)
      self.assertNotIn(("II",), self.tree.B)
  
imports: import pytest
  from holoviews.core.element import AttrTree
  from holoviews.element.comparison import ComparisonTestCase
label_desc: Use image node_id 16 for calling the AttrTreeTest obj's underlying member method code with example usage: obj.test_delitem_on_node() without return types