Drives round taking nearly everything out of Italy, that's the difference (9)
I believe the answer is:
diversity
'the difference' is the definition.
(diversity is a kind of difference)
'drives round taking nearly everything out of italy' is the wordplay.
I cannot really understand how this works, but
an anagram of 'drives' is 'divers' which is located in the answer.
'italy' could be 'it' and 'it' is found within the answer.
A single letter 'y' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'that's' acts as a link.
Can you help me to learn more?
(Other definitions for diversity that I've seen before include "Having many different kinds, a variety" , "Variety or miscellany" .)