How to use the pyeapi.api.interfaces function in pyeapi

def __init__(self, *args, **kwargs):
        super(TestApiEthernetInterface, self).__init__(*args, **kwargs)
        self.instance = pyeapi.api.interfaces.EthernetInterface(None)
        self.config = open(get_fixture('running_config.text')).read()

def __init__(self, *args, **kwargs):
        super(TestApiBaseInterface, self).__init__(*args, **kwargs)
        self.instance = pyeapi.api.interfaces.BaseInterface(None)
        self.config = open(get_fixture('running_config.text')).read()

def __init__(self, *args, **kwargs):
        super(TestApiInterfaces, self).__init__(*args, **kwargs)
        self.instance = pyeapi.api.interfaces.Interfaces(None)
        self.config = open(get_fixture('running_config.text')).read()

def __init__(self, *args, **kwargs):
        super(TestApiVxlanInterface, self).__init__(*args, **kwargs)
        self.instance = pyeapi.api.interfaces.VxlanInterface(None)
        self.config = open(get_fixture('running_config.vxlan')).read()

def test_isvalidinterface_returns_true(self):
        func = pyeapi.api.interfaces.isvalidinterface
        for intf in INTERFACES:
            self.assertTrue(func(intf))

def test_instance(self):
        result = pyeapi.api.interfaces.instance(None)
        self.assertIsInstance(result, pyeapi.api.interfaces.Interfaces)

def __init__(self, *args, **kwargs):
        super(TestApiPortchannelInterface, self).__init__(*args, **kwargs)
        self.instance = pyeapi.api.interfaces.PortchannelInterface(None)
        self.config = open(get_fixture('running_config.portchannel')).read()