CHIANG RAI, Thailand (Reuters) - Rescue teams in northern Thailand were giving crash courses in swimming and diving at Tham Luang cave as part of preparations to extract a young soccer squad trapped in a cave and keen to end a harrowing 11-day ordeal. br br A team of divers, medics, counselors and Thai navy SEALS were with the 12 schoolboys and their 25-year-old coach, providing medicines and food while experts assessed conditions for getting them out, a task the government said would not be easy.