code: private <RequestT, ResponseT>
        ServerStreamingCallable<RequestT, ResponseT> createUserFacingServerStreamingCallable(
            String methodName, ServerStreamingCallable<RequestT, ResponseT> inner) {
  
      ServerStreamingCallable<RequestT, ResponseT> traced =
          new TracedServerStreamingCallable<>(
              inner,
              clientContext.getTracerFactory(),
              SpanName.of(TRACING_OUTER_CLIENT_NAME, methodName));
  
      return traced.withDefaultCallContext(clientContext.getDefaultCallContext());
    }
docs: Wraps a callable chain in a user presentable callable that will inject the default call context
  and trace the call.