<PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="10.0.3" />

System.Diagnostics.CodeAnalysis.MemberNotNullAttribute

Specifies that the method or property will ensure that the listed field and property members have not-null values.
namespace System.Diagnostics.CodeAnalysis { internal sealed class MemberNotNullAttribute : Attribute { public string[] Members { get; } public MemberNotNullAttribute(string member); public MemberNotNullAttribute(params string[] members); } }