Append the two labels of metric in a template variable

Can someone help me in this case?

I was trying to use the below query with labels :

I need to get the custom label => label_dp_language + “-” + label_dp_topic
I am expecting output as “eng-USA-GEN” and others values in variable from below query. The issue is same label_values doesnt work with query_result, can someone suggest me how can I append two labels and store in grafana template variable? -


Above query give me all query results with data_value label added to results, now I want this label to be extracted from query so label_values(query_result(…), data_value) should have worked here.