Square distance functions are Polyak-Lojasiewicz and vice-versa

This short note gathers known results to state that the squared distance function to a (nonconvex) closed set of an Euclidean space is Polyak-Lojasiewicz. As a fuzzy reciprocate, we also recall that every Polyak-Lojasiewicz function can be bounded from below by the squared distance function to its set of minimizers.