Print only the number of the difference between dates

Question

I have this:

today = datetime.datetime.now().replace(tzinfo=None).date()
data_add = test.data_add
data_add = data_add.replace(tzinfo=None).date()
difference = today - data_add

this is printing:

622 days, 0:00:00

How can I get only the number 622 though?