def createTopologyNgpf(self, portList, topologyName=None):
        """
        Description
            Create a new Topology and assign ports to it.

        Parameters
            portList: <list>: format = [[(str(chassisIp), str(slotNumber), str(portNumber)] ]
                      Example 1: [ ['192.168.70.10', '1', '1'] ]
                      Example 2: [ ['192.168.70.10', '1', '1'], ['192.168.70.10', '2', '1'] ]

            topologyName: <str>: Give a name to the Topology Group.

        Syntax
            POST: /api/v1/sessions/{id}/ixnetwork/topology

        Return
            /api/v1/sessions/{id}/topology/{id}
        """
        url = self.ixnObj.sessionUrl+'/topology'
        vportList = self.portMgmtObj.getVports(portList)

        if len(vportList) != len(portList):
            raise IxNetRestApiException('createTopologyNgpf: There is not enough vports created to match the number of ports.')

        topologyData = {'vports': vportList}
        if topologyName != None:
            topologyData['name'] = topologyName

        self.ixnObj.logInfo('Create new Topology Group')
        response = self.ixnObj.post(url, data=topologyData)
        topologyObj = response.json()['links'][0]['href']
        return topologyObj