public void ConfigureServices(IServiceCollection services)
{
     Action mduOptions = (opt =>
     {
          opt.CompanyCode = "aaaa";
     });
     services.Configure(mduOptions);
     services.AddSingleton(resolver => resolver.GetRequiredService>().Value);
     services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
}