With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: In 1936, Edward VIII's reign began.
text_B: The is a railway tunnel on the Joetsu Shinkansen on the border of Gunma Prefecture and Niigata Prefecture , Japan .. Joetsu Shinkansen. Joetsu Shinkansen. Gunma Prefecture. Gunma Prefecture. Niigata Prefecture. Niigata Prefecture. In 1978 , the Dai-Shimizu tunnel was completed .. This tunnel was dug for the Joetsu Shinkansen that was to be completed in 1982 .. Joetsu Shinkansen. Joetsu Shinkansen. This tunnel was the world 's longest tunnel at 22,200 m .. During the construction , a fire created a large amount of smoke in the tunnel , and 16 workers died from carbon monoxide poisoning .. carbon monoxide poisoning. carbon monoxide poisoning. When this tunnel was completed , the time between Niigata and Tokyo went down to approximately one hour and forty minutes , three hours faster than using the Joetsu Line .. Joetsu Line. Joetsu Line. Also , when this tunnel was built , natural water was found during construction , which is now sold in bottles .. natural water. spring water
not_related.