code: public Observable<ServiceEndpointPolicyInner> getByResourceGroupAsync(String resourceGroupName, String serviceEndpointPolicyName, String expand) {
          return getByResourceGroupWithServiceResponseAsync(resourceGroupName, serviceEndpointPolicyName, expand).map(new Func1<ServiceResponse<ServiceEndpointPolicyInner>, ServiceEndpointPolicyInner>() {
              @Override
              public ServiceEndpointPolicyInner call(ServiceResponse<ServiceEndpointPolicyInner> response) {
                  return response.body();
              }
          });
      }
docs: Gets the specified service Endpoint Policies in a specified resource group.
  
  @param resourceGroupName The name of the resource group.
  @param serviceEndpointPolicyName The name of the service endpoint policy.
  @param expand Expands referenced resources.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the ServiceEndpointPolicyInner object