Implemented start, stop, suspend and resume client handler methods using _vm_action private method.

        logging.debug('Executed list function with query %s' % query)

        return self._list(query)

    def _vm_action(self, query, method, *args, **kwargs):

        query += '&vm'

        vms = self._list(query)

        hypervisors = list(self._server.iterrole('hypervisor'))

        for hv in hypervisors:

            vm_to_start = [vm['vm'] for vm in vms if vm['hv'] == hv.login]

            if vm_to_start:

                hv.connection.call(method, vm_to_start, *args, **kwargs)

    @pure

    @listed

    def start(self, query):

        self._vm_action(query, 'start_vm')

    @pure

    @listed

    def stop(self, query, force=False):

        self._vm_action(query, 'stop_vm', force)

    @pure

    @listed

    def suspend(self, query):

        self._vm_action(query, 'suspend_vm')

    @pure

    @listed

    def resume(self, query):

        self._vm_action(query, 'resume_vm')

class AuthenticationError(Exception):

    pass