TIL #144 – Sentinel built-in

Today I learned Python 3.15 will get a new sentinel built-in. Sentinel values are unique placeholder values that are commonly used in programming. Python 3.15 ships with a new built-in sentinel that can be used to create new sentinel values: # Python 3.15+ >>> MISSING = sentinel("MISSING") >>> MISSING MISSING Before this built-in was added, the most common sentinel idiom used the built-in object :…