title: Grouping / clustering numbers in Python
body: <p>I've googled, I've tested, and this has me at my wits end. I have a list of numbers I need to group by similarity. For instance, in a list of [1, 6, 9, 100, 102, 105, 109, 134, 139], 1 6 9 would be put into a list, 100, 102, 105, and 109 would be put into a list, and 134 and 139. I'm terrible at math, and I've tried and tried this, but I can't get it to work. To be explicit as possible, I wish to group numbers that are within 10 values away from one another. Can anyone help? Thanks.</p>