Hello, i have stucked, can you please help me with this.
As i understood the dictionary[“inserted”] return an array of objects type any, so i would like to downcast these array to [Location] and the just addAnnotations on the mapView, but xcode says that i couldn’t do this, i don’t understand why, sorry for my English, i’m only learning it. Thank you for answer.
Almost correct. 
The dictionary does not return an array but a set. This is like an array but each object can appear only once and the objects in the set do not appear in any particular order.
Check out the documentation for Set in the Xcode documentation browser.