code: def test_error_conditions(self):
      # Try to open a non-existent database.
      unlink(filename)
      self.assertRaises(gdbm.error, gdbm.open, filename, "r")
      # Try to access a closed database.
      self.g = gdbm.open(filename, "c")
      self.g.close()
      self.assertRaises(gdbm.error, lambda: self.g["a"])
      # try pass an invalid open flag
      self.assertRaises(
          gdbm.error, lambda: gdbm.open(filename, "rx").close()
      )
  
imports: from test import support
  from test.support import import_helper, cpython_only
  import unittest
  import os
  from test.support.os_helper import TESTFN, TESTFN_NONASCII, unlink, FakePath
label_desc: Use image node_id 6 for calling the TestGdbm obj's underlying member method code with example usage: obj.test_error_conditions() without return types