With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Anorexia nervosa is characterized by a fear of gaining weight.
text_B: Petina may refer to  :. Petina , Campania , Italian municipality of the Province of Salerno , Campania. Petina -LRB- Krusevac -RRB- , Serbian village of Krusevac municipality , in Rasina District. Petina , Croatia , a village in the Velika Gorica municipality , Zagreb County
not_related.