Check if a mesh has UV map at runtime

How do you check if a mesh has a UV map (at runtime)?

A mesh always has a UV map- but if it hasn’t been set up properly before exporting it’ll usually be at a default value, which depends on the modelling package it was created in. It’s difficult to tell from scripting whether a UV map is valid or not- it’s the kind of thing that is much easier to tell just by looking at it since humans have much better pattern recognition skills than computers.