code: public Observable<Page<PolicyAssignmentInner>> listAsync(final String filter) {
          return listWithServiceResponseAsync(filter)
              .map(new Func1<ServiceResponse<Page<PolicyAssignmentInner>>, Page<PolicyAssignmentInner>>() {
                  @Override
                  public Page<PolicyAssignmentInner> call(ServiceResponse<Page<PolicyAssignmentInner>> response) {
                      return response.body();
                  }
              });
      }
docs: Gets all the policy assignments for a subscription.
  
  @param filter The filter to apply on the operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;PolicyAssignmentInner&gt; object