[TYPO3] img depend on language

[Vandemaele David]

The site I use Typo3 for has about 15 different languages.
Each language should display a different logo.

I would do the following (i'm using TV):

lib.logo_country = IMAGE
lib.logo_country{
	file = fileadmin/template/images/logos/logo_{here comes the language 
code}.jpg
}

How can I substitute the "{here comes the language code}" so it becomes 
(for example: fileadmin/template/images/logos/logo_15.jpg

Greetings

David