code: def test_intersection(self):
      mask_a = BitMask.from_bin("0b101")
      mask_b = BitMask.from_bin("0b100")
      mask_a.intersection(mask_b)
      self.assertEqual(mask_a.x, int("0b100", 2))
  
imports: import unittest
  from copy import deepcopy
  from random import randint, random, seed
  from lightly.api.bitmask import BitMask
label_desc: Use image node_id 9 for calling the TestBitMask obj's underlying member method code with example usage: obj.test_intersection() without return types