Never use print for debugging again... If you're creating a reasonably complex project, spend some time to set up a nice and robust logging facility and always use it instead of print. That's the first thing you should do. You will not regret that decision.
I sometimes use a debugger to tackle with unfamiliar code, but I always prefer using trace/logging whenever possible, because 1) you can see the context and whole process that reached that point, and 2) the history of debugging can be checked into a VCS. I'd write an one-liner to scan the log file rather than setting up a conditional breakpoint. I particularly like doing this for a GUI application. A regression testing can be done by comparing logs.
I sometimes use a debugger to tackle with unfamiliar code, but I always prefer using trace/logging whenever possible, because 1) you can see the context and whole process that reached that point, and 2) the history of debugging can be checked into a VCS. I'd write an one-liner to scan the log file rather than setting up a conditional breakpoint. I particularly like doing this for a GUI application. A regression testing can be done by comparing logs.