code: def test_pop(self):
      d = self.new_dict(key="value")
  
      # pop() must change the version if the key exists
      self.check_version_changed(d, d.pop, "key")
  
      # pop() must not change the version if the key does not exist
      self.check_version_dont_change(
          d, self.assertRaises, KeyError, d.pop, "key"
      )
  
imports: import unittest
  from test.support import import_helper
label_desc: Use image node_id 13 for calling the DictVersionTests obj's underlying member method code with example usage: obj.test_pop() without return types