def perform_maintenance_async(resource_group_name, vm_scale_set_name, vm_instance_ids:nil, custom_headers:nil)
      # Send request
      promise = begin_perform_maintenance_async(resource_group_name, vm_scale_set_name, vm_instance_ids:vm_instance_ids, custom_headers:custom_headers)

      promise = promise.then do |response|
        # Defining deserialization method.
        deserialize_method = lambda do |parsed_response|
        end

        # Waiting for response.
        @client.get_long_running_operation_result(response, deserialize_method)
      end

      promise
    end
def perform_maintenance_async(resource_group_name, vm_scale_set_name, vm_instance_ids:nil, custom_headers:nil)
      # Send request
      promise = begin_perform_maintenance_async(resource_group_name, vm_scale_set_name, vm_instance_ids:vm_instance_ids, custom_headers:custom_headers)

      promise = promise.then do |response|
        # Defining deserialization method.
        deserialize_method = lambda do |parsed_response|
        end

        # Waiting for response.
        @client.get_long_running_operation_result(response, deserialize_method)
      end

      promise
    end
@param resource_group_name [String] The name of the resource group.
 @param vm_scale_set_name [String] The name of the VM scale set.
 @param vm_instance_ids [VirtualMachineScaleSetVMInstanceIDs] A list of
 virtual machine instance IDs from the VM scale set.
 @param custom_headers [Hash{String => String}] A hash of custom headers that
 will be added to the HTTP request.

 @return [Concurrent::Promise] promise which provides async access to http
 response.