There is a difference between debugging my current code - where I can build a mental model and work with print statements and dealing with other peoples (or my

There is a difference between debugging my current code - where I can build a mental model and work with print statements and dealing with other peoples (or my long past self's) code. With other peoples code I need to restrict myself to partial understanding of the overall state and thus need a more comprehensive view of the local execution context than what a print statement provides.