How to have one list of items be converted into seperate ones in python?

How to have one list of items be converted into seperate ones in python?

How would I take for example some things of a list named b. b =
['9','billy','8','10','Amanda','1'] The list of things are the repeating
the '9' in front of billy is age 'billy' is the name '8' months tell his
birthday what is the most efficient way to have it so it's turned into
separate lists like, [['9','billy','8'],['10','Amanda',1']] ? Using python
of course.