הזיהויים של marylusk

There is a group of these birds that are in a nearby park. They appear to be some type of parakeet or parrot. They have purple heads, purple tail feathers, and purple feathers under their wings. The rest of their bodies are green, including the top of their wings. They also have small rounded orange beaks. I tend to see them in the mornings & evenings in groups. They are very vocal.