code: public Observable<CognitiveServicesAccountKeysInner> listKeysAsync(String resourceGroupName, String accountName) {
          return listKeysWithServiceResponseAsync(resourceGroupName, accountName).map(new Func1<ServiceResponse<CognitiveServicesAccountKeysInner>, CognitiveServicesAccountKeysInner>() {
              @Override
              public CognitiveServicesAccountKeysInner call(ServiceResponse<CognitiveServicesAccountKeysInner> response) {
                  return response.body();
              }
          });
      }
docs: Lists the account keys for the specified Cognitive Services account.
  
  @param resourceGroupName The name of the resource group within the user's subscription.
  @param accountName The name of Cognitive Services account.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the CognitiveServicesAccountKeysInner object