QueryDebugger
(Infrastructure) Implement query debugger services.
            
                using System.Runtime.CompilerServices;
namespace System.Reactive.Linq
{
    public class QueryDebugger : IQueryServices
    {
        [System.Runtime.CompilerServices.NullableContext(1)]
        T IQueryServices.Extend<[System.Runtime.CompilerServices.Nullable(2)] T>(T baseImpl)
        {
            return baseImpl;
        }
    }
}