code: def test_assign_double_nested_tuple(self):
      self.assertEqual(self.layout.updatemenus, ())
  
      # Initialize empty updatemenus
      self.layout.updatemenus = [{}, {}]
  
      # Initialize empty buttons in updatemenu[1]
      self.layout[("updatemenus", 1, "buttons")] = [{}, {}, {}]
  
      # Assign
      self.layout[
          ("updatemenus", 1, "buttons", 2, "method")
      ] = "restyle"
  
      # Check
      self.assertEqual(
          self.layout[("updatemenus", 1, "buttons", 2, "method")],
          "restyle",
      )
  
      d1, d2 = strip_dict_params(self.layout, self.expected_layout2)
      assert d1 == d2
  
imports: from unittest import TestCase
  import plotly.graph_objs
  from plotly.tests.utils import strip_dict_params
label_desc: Use image node_id 6 for calling the TestAssignCompoundArray obj's underlying member method code with example usage: obj.test_assign_double_nested_tuple() without return types