// Available variables:
  // - Machine
  // - interpret
  // - assign
  // - send
  // - sendParent
  // - spawn
  // - raise
  // - actions
  // - XState (all XState exports)
  
  const elevatorMachine = Machine({
    key: "door",
    initial: "closed",
    states: {
      closed: {
        on: {
          OPEN: "open",
          LOCK: "locked"
        }
      },
      open: {
        on: {
          CLOSE: "closed"
        }
      },
      locked: {
        on: {
          UNLOCK: "closed"  
        }
      }
    }
  });