With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Attack on Titan is running.
text_B: Dinitrogen difluoride is a chemical compound with the formula N2F2 .. chemical compound. chemical compound. It is a gas at room temperature , and was first identified in 1952 as the thermal decomposition product of the azide N3F .. thermal decomposition. thermal decomposition. azide. azide. It has the structure F − N = N − F and exists in both a cis - and trans-form .
not_related.