Fill the grid so that every row, every column and every 3x3 box contains the numbers 1 to 9. To see the completed puzzle, buy the next issue of the Guardian (for puzzles published Monday to Thursday).

Learn coding in Python, Go and Rust from Serdar Yegulalp, software dev specialist and senior writer at InfoWorld. You might be familiar with how Python and C can work together, by way of projects like ...