how to fetch data from server in swift
func fetchFilms(completionHandler: @escaping ([Film]) -> Void) {
// Setup the variable lotsOfFilms
var lotsOfFilms: [Film]
// Call the API with some code
// Using data from the API, assign a value to lotsOfFilms
// Give the completion handler the variable, lotsOfFilms
completionHandler(lotsOfFilms)
}