// Factory for SignatureLoadModel.
        private static ITransformer Create(IHostEnvironment env, ModelLoadContext ctx)
        {
            Contracts.CheckValue(env, nameof(env));
            env.CheckValue(ctx, nameof(ctx));
            ctx.CheckAtModel(GetVersionInfo());

            var contractName = ctx.LoadString();

            var          composition = env.GetCompositionContainer();
            ITransformer transformer = composition.GetExportedValue <ITransformer>(contractName);

            return(transformer);
        }