With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Lisa Kudrow refused to work on any shows that aired on Showtime.
text_B: George Henry Challenger -LRB- 1881-1947 -RRB- was a British aviator and aero-engineer , originally with the Bristol Aeroplane Company and later with Vickers .. aero-engineer. Aerospace engineering. He designed a number of aircraft and held a number of aviation-related patents .
not_related.