With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Afghanistan is the source of the Kushan Empire, which ruled during the 1st century.
text_B: Pejantan Tangguh is music album from Sheila on 7 released in 2004 .. Sheila on 7. Sheila on 7. It contains the singles , `` Pejantan Tangguh '' and `` Itu Aku '' .
not_related.