/// <summary>
        /// Writes the responses as a ChangeSet.
        /// </summary>
        /// <param name="writer">The <see cref="ODataBatchWriter"/>.</param>
        /// <param name="cancellationToken">The token to monitor for cancellation requests.</param>
        public override async Task WriteResponseAsync(ODataBatchWriter writer, CancellationToken cancellationToken)
        {
            if (writer == null)
            {
                throw Error.ArgumentNull("writer");
            }

            writer.WriteStartChangeset();

            foreach (HttpResponseMessage responseMessage in Responses)
            {
                await WriteMessageAsync(writer, responseMessage, cancellationToken);
            }

            writer.WriteEndChangeset();
        }