In Python 3, error handling is managed through , which are events that disrupt the normal flow of a program . Mastering these tools allows you to create robust applications that can recover from issues like invalid user input or missing files instead of crashing. The Core Mechanism: try...except
For more complex logic, Python provides two optional clauses: Python 3: Handling errors
: Use the raise keyword to manually trigger an exception when a specific condition isn't met. In Python 3, error handling is managed through
: Runs only if the code in the try block executed without any exceptions. Use this for code that should only run if the "risky" part succeeded. : Runs only if the code in the
: Always runs regardless of whether an error occurred. This is essential for resource cleanup , such as closing files or database connections. Strategic Techniques
: For domain-specific logic, you can define your own error classes by inheriting from the built-in Exception class.
: Pythonic code often follows "Easier to Ask Forgiveness than Permission" (EAFP)—trying an operation and handling the failure rather than checking if it's possible beforehand. Common Built-in Exceptions