With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Avril Lavigne joined Greenpeace.
text_B: A.O. Karditsa F.C. is a Greek football club , based in Karditsa , Karditsa .. Karditsa. Karditsa ( regional unit ). Greek. Greece. football. Football ( soccer )
not_related.