this code give the errors that i added at the and. can you correct the code

package observer.log

import scala.collection.mutable.$\{$Set $=>$ mSet, ListBuffer$\}$

trait Loggable$[$Subject$,$ Delta$]$:

val observers: ListBuffer$[$LoggingObserver$[$Subject$,$ Delta$]]=$ ListBuffer.empty

private var timestamp: Long $=\_$

def attach$($observer: LoggingObserver$[$Subject$,$ Delta$])$: Unit $=\{$

observers $+=$ observer

$\}$

def notifyAllObservers$()$: Unit $=\{$

timestamp $=$ System.currentTimeMillis$()$

observers.foreach$($observ