code: public Observable<PolicyAssignmentInner> getAsync(String scope, String policyAssignmentName) {
          return getWithServiceResponseAsync(scope, policyAssignmentName).map(new Func1<ServiceResponse<PolicyAssignmentInner>, PolicyAssignmentInner>() {
              @Override
              public PolicyAssignmentInner call(ServiceResponse<PolicyAssignmentInner> response) {
                  return response.body();
              }
          });
      }
docs: Gets a policy assignment.
  
  @param scope The scope of the policy assignment.
  @param policyAssignmentName The name of the policy assignment to get.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PolicyAssignmentInner object