<PackageReference Include="System.Collections.Immutable" Version="11.0.0-preview.1.26104.118" />

System.Runtime.CompilerServices.OverloadResolutionPriorityAttribute

namespace System.Runtime.CompilerServices { internal sealed class OverloadResolutionPriorityAttribute : Attribute { public int Priority { get; } public OverloadResolutionPriorityAttribute(int priority); } }