How to use the approvaltests.reporters.testing_reporter.ReporterForTesting function in approvaltests

def test_returns_error_when_files_are_different(self):
        namer = get_default_namer()
        writer = StringWriter("b")
        reporter = ReporterForTesting()
        approver = FileApprover()
        error = approver.verify(namer, writer, reporter)
        self.assertEqual("Approval Mismatch", error)

def test_compare_different_files(self):
        approver = FileApprover()
        reporter = ReporterForTesting()
        approver.verify_files("a.txt", "b.txt", reporter)
        self.assertTrue(reporter.called)

def setUp(self):
        self.reporter = ReporterForTesting()
        self.reporter = CommandLineReporter()
        self.func = lambda *args: sum(args) + 1

def test_assert_against_file_fails_with_reporter(self):
        reporter = ReporterForTesting()
        file_path = get_adjacent_file("manual_file.approved.txt")
        try:
            assert_against_file("This text is NOT in a file", file_path, reporter )
        except ApprovalException:
            pass
        self.assertTrue(reporter.called)

def test_full(self):
        namer = get_default_namer()
        writer = StringWriter("b")
        reporter = ReporterForTesting()
        approver = FileApprover()
        approver.verify(namer, writer, reporter)
        self.assertTrue(reporter.called)

def setUp(self):
        self.reporter = ReporterForTesting()
        self.func = lambda *args: sum(args) + 1

def test_verify_fail(self):
        reporter = ReporterForTesting()
        try:
            verify("Hello World.", reporter)
            self.assertFalse(True, "expected exception")
        except ApprovalException as e:
            self.assertTrue("Approval Mismatch", e.value)