il generation

        public void CreateModelFactory()
        {
            var modelType = typeof(TImportModel);

            var constructor = typeof(TImportModel).GetConstructor(new[] { typeof(int) });
            if (constructor == null)
            {
                throw new MissingMethodException($"There is no constructor with the signature '(int)' for type '{modelType}'");
            }
            DynamicMethod dynamic = new DynamicMethod(name: string.Empty,
                                                      returnType: modelType,
                                                      parameterTypes: new[] { typeof(int) },
                                                      owner: modelType);
            ILGenerator il = dynamic.GetILGenerator();

            il.DeclareLocal(modelType);
            il.Emit(OpCodes.Ldarg_0);
            il.Emit(OpCodes.Newobj, constructor);
            il.Emit(OpCodes.Ret);

            _modelFactory = (Func<int, TImportModel>)dynamic.CreateDelegate(typeof(Func<int, TImportModel>));
        }