Test It in Isolation, but Also Use Values That Make Sense

Mokkaru.com is a place where you can ask for all types of data and it'll generate as many of those as you want. So I could ask for like cars, VIN numbers or let's see for commerce. There's a couple of plugins I know for Django that do something similar meant exactly for that same reason. Like testing often is people espouse like testing in isolation and testing just this part or that part. But don't think this point is talked about enough, which is like test it in isolation, but also use values that make sense.