code: public Observable<Page<ContainerGroupInner>> listAsync() {
          return listWithServiceResponseAsync()
              .map(new Func1<ServiceResponse<Page<ContainerGroupInner>>, Page<ContainerGroupInner>>() {
                  @Override
                  public Page<ContainerGroupInner> call(ServiceResponse<Page<ContainerGroupInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get a list of container groups in the specified subscription.
  Get a list of container groups in the specified subscription. This operation returns properties of each container group including containers, image registry credentials, restart policy, IP address type, OS type, state, and volumes.
  
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;ContainerGroupInner&gt; object