user: Question: Name the Nationality / Opponent of the Competition of Welsh Rugby Union Challenge Trophy and a Result of 38-29?
Columns: ['Date', 'Nationality / Opponent', 'Ground', 'Result', 'Competition']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['21 October 1989', 'New Zealand', 'Saint Helens Cricket and Football Ground, Swansea', '22-37', 'New Zealand Tour of Great Britain and Ireland 1989']
SQL:

assistant: SELECT "Nationality / Opponent" FROM "Table" WHERE "Competition" = 'Welsh Rugby Union Challenge Trophy' AND "Result" = '38-29';