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Utilize Python’s `logging.Logger` class to easily track events and debug your program with customizable log messages.

# Python Class logging.Logger Usage

Logging in Python is a useful way to keep track of events that occur during the execution of a program. The `logging` module provides a flexible and powerful logging system that can be customized to suit the needs of your application. One of the key components of the `logging` module is the `Logger` class, which is used to create loggers that can be used to log messages at various levels of severity.

## Creating a Logger

To create a `Logger` object in Python, you first need to import the `logging` module:

“`python
import logging
“`

Once you have imported the `logging` module, you can create a `Logger` object by calling the `logging.getLogger()` method:

“`python
logger = logging.getLogger(‘my_logger’)
“`

In the example above, we have created a `Logger` object named ‘my_logger’. You can use any name you like for your logger, but it is a good practice to give it a descriptive name that reflects the purpose of the logger.

## Logging Messages

Once you have created a `Logger` object, you can use it to log messages at different levels of severity. The `logging` module defines several logging levels, including `DEBUG`, `INFO`, `WARNING`, `ERROR`, and `CRITICAL`. You can log messages at a specific level by calling the corresponding method on the `Logger` object:

“`python
logger.debug(‘This is a debug message’)
logger.info(‘This is an info message’)
logger.warning(‘This is a warning message’)
logger.error(‘This is an error message’)
logger.critical(‘This is a critical message’)
“`

In the example above, we are logging messages at various levels of severity using the `Logger` object we created earlier. The messages will be displayed in the console or written to a log file, depending on how you have configured the logging system.

## Configuring the Logger

By default, the `Logger` object will log messages at the `WARNING` level and above. If you want to change the logging level or configure other aspects of the logging system, you can do so by creating a `logging` configuration. Here is an example of how you can configure the `Logger` object:

“`python
logging.basicConfig(level=logging.DEBUG)
“`

In the example above, we have set the logging level to `DEBUG`, which means that all messages at the `DEBUG` level and above will be logged. You can customize the logging configuration further by specifying a format for the log messages, adding handlers to write messages to different destinations, and more.

## Adding Handlers

Handlers are objects that define where the log messages should be sent. The `logging` module provides several built-in handler classes, such as `StreamHandler` for writing messages to the console and `FileHandler` for writing messages to a file. You can add a handler to a `Logger` object by calling the `addHandler()` method:

“`python
file_handler = logging.FileHandler(‘app.log’)
logger.addHandler(file_handler)
“`

In the example above, we have created a `FileHandler` object that will write log messages to a file named ‘app.log’. We then added the handler to our `Logger` object so that messages will be written to the file in addition to being displayed in the console.

## Conclusion

In this guide, we have covered the basics of using the `logging.Logger` class in Python. Logging is an essential tool for debugging and monitoring the behavior of your applications, and the `logging` module provides a powerful and flexible logging system that can be customized to suit your needs. By creating a `Logger` object, logging messages at different levels of severity, configuring the logger, and adding handlers, you can create a robust logging system that will help you track down bugs and troubleshoot issues in your code.