`Exception`

Exception is a built-in exception that serves as the base class for all built-in exceptions except for system-exiting exceptions.

It’s itself a subclass of BaseException. Exception is an important part of Python’s class hierarchy for exceptions, which helps you organize error handling in a structured way.

You’d typically use this exception as a base class for your own custom exceptions. By subclassing Exception, you ensure that your custom exceptions integrate smoothly with Python’s exception-handling mechanism. This allows you to handle errors and unexpected events effectively.

`Exception` Occurs When

The Exception class itself doesn’t appear unless you raise it explicitly.

`Exception` Can Be Used When

Creating custom exceptions for your application
Handling a broad range of exceptions in a single except block
Ensuring that exceptions integrate with Python’s built-in exception hierarchy

`Exception` Examples

It’s common to subclass Exception to create more specific exceptions:

Python
      
        
      
    
>>> class CustomError(Exception):
...     pass
...

>>> try:
...     raise CustomError("This is a custom error")
... except CustomError as e:
...     print(e)
...
This is a custom error

Below is a way to handle exceptions by catching them under a general Exception clause:

Python
      
        
      
    
>>> import random

>>> def raise_random_error():
...     errors = [
...         ValueError("This is a ValueError"),
...         TypeError("This is a TypeError"),
...         IndexError("This is an IndexError")
...     ]
...     raise random.choice(errors)
...

>>> try:
...     raise_random_error()
... except Exception as e:
...     print(f"Caught an exception: {e}")
...
Caught an exception: This is a TypeError

The raise_random_error() function raises a random exception from the errors list. You can then handle any of these exceptions with a single except Exception block. This works because all of these exceptions inherit from Exception.

It’s recommended to raise more specific exceptions instead of the Exception class, but you can use Exception if you need a general-purpose error indicator.

Tutorial

Python's Built-in Exceptions: A Walkthrough With Examples

In this tutorial, you'll get to know some of the most commonly used built-in exceptions in Python. You'll learn when these exceptions can appear in your code and how to handle them. Finally, you'll learn how to raise some of these exceptions in your code.

intermediate python

For additional information on related topics, take a look at the following resources: