<PackageReference Include="Polly.Core" Version="8.6.6" />

System.Collections.Concurrent.ConcurrentDictionaryExtensions

namespace System.Collections.Concurrent { internal static class ConcurrentDictionaryExtensions { public static TValue GetOrAdd<[System.Runtime.CompilerServices.Nullable(2)] TKey, [System.Runtime.CompilerServices.Nullable(2)] TValue, [System.Runtime.CompilerServices.Nullable(2)] TArg>(this ConcurrentDictionary<TKey, TValue> dictionary, TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument); } }