Stashbox by Peter Csajtai

<PackageReference Include="Stashbox" Version="3.6.2-preview-635" />

 Pair<T1, T2>

class Pair<T1, T2>
namespace Stashbox.Utils.Data { internal class Pair<T1, T2> { public T1 I1; public T2 I2; public Pair(T1 item1, T2 item2) { I1 = item1; I2 = item2; } } }