system/Config/Services.php
public static function logger(bool $getShared = true)
	{
		if ($getShared)
		{
			return static::getSharedInstance('logger');
		}

		return new \CodeIgniter\Log\Logger(new Logger());
	}
public static function logger(bool $getShared = true)
	{
		if ($getShared)
		{
			return static::getSharedInstance('logger');
		}

		return new \CodeIgniter\Log\Logger(new Logger());
	}
The Logger class is a PSR-3 compatible Logging class that supports
multiple handlers that process the actual logging.

@param boolean $getShared

@return \CodeIgniter\Log\Logger