How to use the nose2.util.test_from_name function in nose2

def loadTestsFromName(self, event):
        """Load tests from event.name if it names a test case/method"""
        name = event.name
        module = event.module
        log.debug("load %s from %s", name, module)
        try:
            result = util.test_from_name(name, module)
        except (AttributeError, ImportError):
            event.handled = True
            return event.loader.failedLoadTests(name, sys.exc_info())
        if result is None:
            return
        parent, obj, name, index = result
        if isinstance(obj, type) and issubclass(obj, unittest.TestCase):
            # name is a test case class
            event.extraTests.append(self._loadTestsFromTestCase(event, obj))
        elif (isinstance(parent, type) and
              issubclass(parent, unittest.TestCase) and
              not util.isgenerator(obj) and
              not hasattr(obj, 'paramList')):
            # name is a single test method
            event.extraTests.append(parent(obj.__name__))

def loadTestsFromName(self, event):
        """Load tests from event.name if it names a test class/method"""
        name = event.name
        module = event.module
        try:
            result = util.test_from_name(name, module)
        except (AttributeError, ImportError):
            event.handled = True
            return event.loader.failedLoadTests(name, sys.exc_info())
        if result is None:
            return
        parent, obj, name, index = result
        if isinstance(obj, type) and not issubclass(obj, unittest.TestCase):
            # name is a test case class
            event.extraTests.append(self._loadTestsFromTestClass(event, obj))
        elif (isinstance(parent, type) and
              not issubclass(parent, unittest.TestCase) and
              not util.isgenerator(obj) and
              not hasattr(obj, 'paramList')):
            # name is a single test method
            event.extraTests.append(
                util.transplant_class(

def loadTestsFromName(self, event):
        """Load parameterized test named on command line"""
        original_name = name = event.name
        module = event.module
        try:
            result = util.test_from_name(name, module)
        except (AttributeError, ImportError):
            event.handled = True
            return event.loader.failedLoadTests(name, sys.exc_info())
        if result is None:
            # we can't find it - let the default case handle it
            return

        parent, obj, fqname, index = result
        if not hasattr(obj, 'paramList'):
            return

        if (index is None and not
            isinstance(parent, type) and not
            isinstance(obj, types.FunctionType)):
            log.debug(
                "Don't know how to load parameterized tests from %s", obj)

def loadTestsFromName(self, event):
        """Load test if event.name is the name of a test function"""
        name = event.name
        module = event.module
        try:
            result = util.test_from_name(name, module)
        except (AttributeError, ImportError):
            event.handled = True
            return event.loader.failedLoadTests(name, sys.exc_info())
        if result is None:
            return

        parent, obj, name, index = result
        if (isinstance(obj, types.FunctionType) and not
            util.isgenerator(obj) and not
            hasattr(obj, 'paramList') and
            util.num_expected_args(obj) == 0):
            suite = event.loader.suiteClass()
            suite.addTests(self._createTests(obj))
            event.handled = True
            return suite

def loadTestsFromName(self, event):
        """Load tests from generator named on command line"""
        original_name = name = event.name
        module = event.module
        try:
            result = util.test_from_name(name, module)
        except (AttributeError, ImportError):
            event.handled = True
            return event.loader.failedLoadTests(name, sys.exc_info())
        if result is None:
            # we can't find it - let the default case handle it
            return

        parent, obj, name, index = result
        if not util.isgenerator(obj):
            return

        if (index is None and not
            isinstance(parent, type) and not
            isinstance(obj, types.FunctionType)):
            log.debug("Don't know how to load generator tests from %s", obj)
            return