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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def transport_service(self, **kwargs):
 """Configure VLAN Transport Service. Args: vlan (str):
 The VLAN ID. service_id (str):
 The transport-service ID. callback (function):
 A function executed upon completion of the method. The only parameter passed to `callback` will be the ``ElementTree`` `config`. Returns: Return value of `callback`. Raises: KeyError: if `vlan` or `service_id` is not specified. ValueError: if `vlan` is invalid. Examples: """

        vlan = kwargs.pop('vlan')
        service_id = kwargs.pop('service_id')
        callback = kwargs.pop('callback', self._callback)

        if not pynos.utilities.valid_vlan_id(vlan, extended=True):
            raise InvalidVlanId("vlan must be between `1` and `8191`")

        service_args = dict(name=vlan, transport_service=service_id)
        transport_service = getattr(self._interface,
                                    'interface_vlan_interface_vlan_'
                                    'transport_service')
        config = transport_service(**service_args)
        return callback(config)