/// <summary>
 /// Creates, updates, or removes extension feed items. Operation
 /// statuses are returned.
 /// </summary>
 /// <param name="request">The request object containing all of the parameters for the API call.</param>
 /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
 /// <returns>A Task containing the RPC response.</returns>
 public override stt::Task <MutateExtensionFeedItemsResponse> MutateExtensionFeedItemsAsync(MutateExtensionFeedItemsRequest request, gaxgrpc::CallSettings callSettings = null)
 {
     Modify_MutateExtensionFeedItemsRequest(ref request, ref callSettings);
     return(_callMutateExtensionFeedItems.Async(request, callSettings));
 }
 /// <summary>
 /// Creates, updates, or removes extension feed items. Operation
 /// statuses are returned.
 /// </summary>
 /// <param name="request">The request object containing all of the parameters for the API call.</param>
 /// <param name="cancellationToken">A <see cref="st::CancellationToken"/> to use for this RPC.</param>
 /// <returns>A Task containing the RPC response.</returns>
 public virtual stt::Task <MutateExtensionFeedItemsResponse> MutateExtensionFeedItemsAsync(MutateExtensionFeedItemsRequest request, st::CancellationToken cancellationToken) =>
 MutateExtensionFeedItemsAsync(request, gaxgrpc::CallSettings.FromCancellationToken(cancellationToken));
 partial void Modify_MutateExtensionFeedItemsRequest(ref MutateExtensionFeedItemsRequest request, ref gaxgrpc::CallSettings settings);
 /// <summary>
 /// Creates, updates, or removes extension feed items. Operation
 /// statuses are returned.
 /// </summary>
 /// <param name="request">The request object containing all of the parameters for the API call.</param>
 /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
 /// <returns>A Task containing the RPC response.</returns>
 public virtual stt::Task <MutateExtensionFeedItemsResponse> MutateExtensionFeedItemsAsync(MutateExtensionFeedItemsRequest request, gaxgrpc::CallSettings callSettings = null) =>
 throw new sys::NotImplementedException();