Put quotes around strings between commas, but not numbers

So I have some text in a file that almost represents CSV format, but not entirely. I want to turn in into a CSV file though. I have for example: cuz,0,1,2,3,-4,abc,a b c,0 How can I turn that into "cuz",0,1,2,3,-4,"abc","a b c",0 Any help would be appreciated! Thanks in advance.