With no explanation, label text_A→text_B with either "entailment", "neutral" or "contradiction".
text_A: The J-20 made its maiden flight on 11 January 2011, but the plane was officially revealed on China International Aviation & Aerospace Exhibition in 2016.
text_B: The J-21 made its maiden flight on 11 January 2011, but the plane was officially revealed on China International Aviation & Aerospace Exhibition in 2016.
contradiction.