How to use the messagebird.call_flow.CallFlow function in messagebird

def call_flow_update(self, id, title, steps, default, record):
        params = {'title': title, 'steps': steps, 'default': default, 'record': record}
        return CallFlow().load(self.request('call-flows/' + str(id), 'PUT', params, VOICE_TYPE))

def __init__(self):
        self._data = None
        self._pagination = None

        super(CallFlowList, self).__init__(CallFlow)

def call_flow(self, id):
        return CallFlow().load(self.request('call-flows/' + str(id), 'GET', None, VOICE_TYPE))

def call_flow_create(self, title, steps, default=False, record=False):
        params = {'title': title, 'steps': steps, 'default': default, 'record': record}
        return CallFlow().load(self.request('call-flows', 'POST', params, VOICE_TYPE))