Please see the code:
let calendarName = "My calendar"
let cal = await Calendar.forEventsByTitle(calendarName)
// Works fine https://talk.automators.fm/t/1401
let e = await CalendarEvent.thisWeek([cal])
// Error: Cannot call a class constructor without |new|
let e = await CalendarEvent().between(new Date("2019"), new Date(), [cal])
// Error: new CalendarEvent().between is not a function
let e = await new CalendarEvent().between(new Date("2019"), new Date(), [cal])