code: def test_mutable_entry(self):
      d1 = byteskeydict()
      with shelve.Shelf(d1, protocol=2, writeback=False) as s:
          s["key1"] = [1, 2, 3, 4]
          self.assertEqual(s["key1"], [1, 2, 3, 4])
          s["key1"].append(5)
          self.assertEqual(s["key1"], [1, 2, 3, 4])
  
      d2 = byteskeydict()
      with shelve.Shelf(d2, protocol=2, writeback=True) as s:
          s["key1"] = [1, 2, 3, 4]
          self.assertEqual(s["key1"], [1, 2, 3, 4])
          s["key1"].append(5)
          self.assertEqual(s["key1"], [1, 2, 3, 4, 5])
  
      self.assertEqual(len(d1), 1)
      self.assertEqual(len(d2), 1)
  
imports: import unittest
  import dbm
  import shelve
  import pickle
  import os
  from test.support import os_helper
  from collections.abc import MutableMapping
  from test.test_dbm import dbm_iterator
  from test import mapping_tests
label_desc: Use image node_id 10 for calling the TestCase obj's underlying member method code with example usage: obj.test_mutable_entry() without return types