With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Caroline, Princess of Hanover is married to a prince.
text_B: Formula Challenge Japan is an open wheel racing series based in Japan .. Japan. Japan. open wheel racing. open wheel racing. The first season was in 2006 and carried on from the defunct Formula Dream series .. Formula Dream. Formula Dream. It is promoted as a young driver development project jointly by Honda , Toyota and Nissan and is positioned as an intermediate level of the domestic motorsport in Japan , lower than the All-Japan Formula Three Championship , but above F4 .. Japan. Japan. Honda. Honda. Toyota. Toyota. Nissan. Nissan. All-Japan Formula Three Championship. All-Japan Formula Three Championship. Formula Challenge Japan ended after the 2013 season , and was replaced by Japan Formula 4 .. Japan. Japan. Japan Formula 4. Japan Formula 4
not_related.