code: def test_write_write_read(self):
      # test for bug #482460
      with contextlib.closing(dumbdbm.open(_fname)) as f:
          f[b"1"] = b"hello"
          f[b"1"] = b"hello2"
      with contextlib.closing(dumbdbm.open(_fname)) as f:
          self.assertEqual(f[b"1"], b"hello2")
  
imports: import contextlib
  import io
  import operator
  import os
  import stat
  import unittest
  import dbm.dumb
  from test import support
  from test.support import os_helper
  from functools import partial
label_desc: Use image node_id 8 for calling the DumbDBMTestCase obj's underlying member method code with example usage: obj.test_write_write_read() without return types