Sets the specified port as an ACCESS port.

        :param port_number: allocated port number
        :param vlan_id: VLAN number membership

def set_access_port(self, port_number, vlan_id):
        """
        Sets the specified port as an ACCESS port.

        :param port_number: allocated port number
        :param vlan_id: VLAN number membership
        """

        if port_number not in self._nios:
            raise DynamipsError("Port {} is not allocated".format(port_number))

        nio = self._nios[port_number]
        yield from self._hypervisor.send('ethsw set_access_port "{name}" {nio} {vlan_id}'.format(name=self._name,
                                                                                                 nio=nio,
                                                                                                 vlan_id=vlan_id))

        log.info('Ethernet switch "{name}" [{id}]: port {port} set as an access port in VLAN {vlan_id}'.format(name=self._name,
                                                                                                               id=self._id,
                                                                                                               port=port_number,
                                                                                                               vlan_id=vlan_id))
        self._mappings[port_number] = ("access", vlan_id)