How to get language name?

If I use get_bloginfo('language') I get it-IT as a result, but how can I get the name of the language, both in English and in local language?
I mean:

1. is there a function that given it-IT as input returns its local name (“Italiano”)?
2. is there a function that given it-IT as input returns its English name (“Italian”)?

Obvously the question is related to all languages.