Dinosaurs roaming

After a failed dinosaur park carnivores and herbivores were set free into the human world. at first it was tough to survive with free roam dinosaurs but soon jobs were introduced to build walls around major cities and some towns. these walls protect people from larger carnivores as well as large herbivores. smaller dinosaurs however are allowed to roam the cities due to humans keeping them as pets, though permits are needed to own carnivores. (you can live wherever you want and be whatever you want, obviously. add whatever dinos you want as well)