Job Ready Python

Lesson 22Handling Exceptions

Errors detected during the program execution are called exceptions. Specifically, an exception is an event that occurs during the execution of a program, disrupting the normal flow of the program's instructions. Error detection is distinguished from detection of syntax errors (like incorrect indents or missing colons), which prevent the code from running at all.

LEARNING OBJECTIVES

By the end of this lesson, you will be able to:

• Define custom exception messages that will display when Python encounters an error in the code.
• Use try:except to display a message based on the type of error Python encounters.
• Use try:except:finally to continue running a script after Python has encountered an error.

Exception handling is one of the most important features of programming, allowing developers to handle runtime errors caused by exceptions. In this lesson, we will explore exception handling and use examples to demonstrate how to handle exceptions in Python. Exceptions can be handled by implementing proper exception-handling techniques within the code itself. Python allows programmers to implement their own exception-handling techniques as well as to take advantage of built-in exception handlers. Key terms related to this lesson that you should be aware of are the following:

• Exception handling is code designed to handle interruptions in the normal flow of the program execution.
• Try block is code that allows developers to test a code block for errors. ...