code: public Observable<UserInner> updateAsync(String resourceGroupName, String labAccountName, String labName, String userName, UserFragment user) {
          return updateWithServiceResponseAsync(resourceGroupName, labAccountName, labName, userName, user).map(new Func1<ServiceResponse<UserInner>, UserInner>() {
              @Override
              public UserInner call(ServiceResponse<UserInner> response) {
                  return response.body();
              }
          });
      }
docs: Modify properties of users.
  
  @param resourceGroupName The name of the resource group.
  @param labAccountName The name of the lab Account.
  @param labName The name of the lab.
  @param userName The name of the user.
  @param user The User registered to a lab
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the UserInner object