code: public Observable<Page<RoleDefinitionInner>> listAsync(final String scope, final String filter) {
          return listWithServiceResponseAsync(scope, filter)
              .map(new Func1<ServiceResponse<Page<RoleDefinitionInner>>, Page<RoleDefinitionInner>>() {
                  @Override
                  public Page<RoleDefinitionInner> call(ServiceResponse<Page<RoleDefinitionInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Get all role definitions that are applicable at scope and above.
  
  @param scope The scope of the role definition.
  @param filter The filter to apply on the operation. Use atScopeAndBelow filter to search below the given scope as well.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;RoleDefinitionInner&gt; object