With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The stratosphere is a layer of Earth's atmosphere.
text_B: Yoshizawa Ayame is a stage name taken on by a series of Kabuki actors in Japan .. Kabuki. Kabuki. Founded by one of the most famous onnagata -LRB- specialists in female roles -RRB- of all time , three of the four actors to succeed him were his direct relatives .. onnagata. Oyama ( Japanese theatre )
not_related.