@Override
            public ApiFuture<ListTensorFlowVersionsPagedResponse> getFuturePagedResponse(
                UnaryCallable<ListTensorFlowVersionsRequest, ListTensorFlowVersionsResponse>
                    callable,
                ListTensorFlowVersionsRequest request,
                ApiCallContext context,
                ApiFuture<ListTensorFlowVersionsResponse> futureResponse) {
              PageContext<
                      ListTensorFlowVersionsRequest,
                      ListTensorFlowVersionsResponse,
                      TensorFlowVersion>
                  pageContext =
                      PageContext.create(
                          callable, LIST_TENSOR_FLOW_VERSIONS_PAGE_STR_DESC, request, context);
              return ListTensorFlowVersionsPagedResponse.createAsync(pageContext, futureResponse);
            }
The default scopes of the service.
java-tpu/google-cloud-tpu/src/main/java/com/google/cloud/tpu/v1/stub/TpuStubSettings.java