Python provides for the raising and handling of exceptions. An exception is used primarily for managing an error situation, but is also handy in other circumstances e.g. an exception is used internally to end loop iteration.
A full writeup for this presentation is available here.
It’s been a while so first a short(ish) recap of the previous 3 presentations, including in more detail the Input And Output section of session 3. Then I’ll discuss some useful Python Tutorials. And finally we can go on to cover some further aspects of the language.