Gets the info of BGPSpeaker instance.

        Usage:

            ======= ================
            Method  URI
            ======= ================
            GET     /vtep/speakers
            ======= ================

        Example::

            $ curl -X GET http://localhost:8080/vtep/speakers |
             python -m json.tool

        ::

            {
                "172.17.0.1": {
                    "EvpnSpeaker": {
                        "as_number": 65000,
                        "dpid": 1,
                        "neighbors": {
                            "172.17.0.2": {
                                "EvpnNeighbor": {
                                    "address": "172.17.0.2",
                                    "remote_as": 65000,
                                    "state": "up"
                                }
                            }
                        },
                        "router_id": "172.17.0.1"
                    }
                }
            }

def get_speakers(self, **kwargs):
        """
        Gets the info of BGPSpeaker instance.

        Usage:

            ======= ================
            Method  URI
            ======= ================
            GET     /vtep/speakers
            ======= ================

        Example::

            $ curl -X GET http://localhost:8080/vtep/speakers |
             python -m json.tool

        ::

            {
                "172.17.0.1": {
                    "EvpnSpeaker": {
                        "as_number": 65000,
                        "dpid": 1,
                        "neighbors": {
                            "172.17.0.2": {
                                "EvpnNeighbor": {
                                    "address": "172.17.0.2",
                                    "remote_as": 65000,
                                    "state": "up"
                                }
                            }
                        },
                        "router_id": "172.17.0.1"
                    }
                }
            }
        """
        try:
            body = self.vtep_app.get_speaker()
        except BGPSpeakerNotFound as e:
            return e.to_response(status=404)

        return Response(content_type='application/json',
                        body=json.dumps(body))