code: def testBoundingBox(self):
      layout = Layout([(0, 1), (2, 7)])
      self.assertEqual(layout.bounding_box(), BoundingBox(0, 1, 2, 7))
      self.assertEqual(layout.bounding_box(1), BoundingBox(-1, 0, 3, 8))
      layout = Layout([])
      self.assertEqual(layout.bounding_box(), BoundingBox(0, 0, 0, 0))
  
imports: import unittest
  from math import hypot
  from igraph import Graph, Layout, BoundingBox, InternalError
  from igraph import umap_compute_weights
label_desc: Use image node_id 7 for calling the LayoutTests obj's underlying member method code with example usage: obj.testBoundingBox() without return types