With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Jim Crow laws were enacted in the southern United States.
text_B: The was a Japanese amphibious tank built in 1945 .. tank. tank. The To-Ku was large and heavy ; it boasted extensive armor protection with 50 mm of armor plate in the front hull .. The turret was a modified version of the one used on the Type 97 Shinhoto Chi-Ha medium tank and fitted with a Type 1 25 mm gun and a rear facing Type 97 7.7 mm machine gun .. tank. tank. Type 97 Shinhoto Chi-Ha. Type 97 Shinhoto Chi-Ha. Type 97 7.7 mm machine gun. Type 97 heavy tank machine gun. The front hull mounted a Type 1 47 mm tank gun and a Type 97 7.7 mm machine gun .. tank. tank. Type 97 7.7 mm machine gun. Type 97 heavy tank machine gun. Type 1 47 mm tank gun. Type 1 47 mm tank gun. The chassis was based on the Type 5 Chi-Ri medium tank and the suspension , pontoons and propulsion system were substantially the same as the Type 3 Ka-Chi .. tank. tank. Type 5 Chi-Ri. Type 5 Chi-Ri. Type 3 Ka-Chi. Type 3 Ka-Chi. Only one prototype was built of this amphibious tank .. tank. tank
not_related.