With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Rafael Nadal is a League of Legends player.
text_B: Anisus leucostoma is a European species of small air-breathing freshwater snail , an aquatic pulmonate gastropod in the family Planorbidae , the ram 's horn snails and their allies .. Planorbidae. Planorbidae. Anisus. Anisus. species. species. freshwater snail. freshwater snail. aquatic. Aquatic animal. pulmonate. pulmonate. gastropod. gastropod. ram. Ovis
not_related.