Error Handling and Exceptions in Python
Explains Python's exception model and how try-except blocks prevent crashes by catching specific errors like ValueError and ZeroDivisionError. Covers grouping multiple exception types in one except clause, using finally to guarantee cleanup code runs regardless of outcome (demonstrated with file closing), and proactively raising exceptions with the raise keyword to enforce preconditions. Also shows how to define custom exception classes by subclassing Exception, and closes with a calculator exercise that handles invalid input and division by zero.