public static System.Runtime.CompilerServices.ConfiguredCancelableAsyncEnumerable <T> ConfigureAwait <T>(this System.Collections.Generic.IAsyncEnumerable <T> source, bool continueOnCapturedContext)
 {
     throw null;
 }
 public static System.Runtime.CompilerServices.ConfiguredCancelableAsyncEnumerable <T> WithCancellation <T>(this System.Collections.Generic.IAsyncEnumerable <T> source, System.Threading.CancellationToken cancellationToken)
 {
     throw null;
 }
 public static System.Threading.Tasks.Task ForEachAsync <TSource>(System.Collections.Generic.IAsyncEnumerable <TSource> source, System.Threading.Tasks.ParallelOptions parallelOptions, System.Func <TSource, CancellationToken, ValueTask> body)
 {
     throw null;
 }