Consider the following Python code implementing a thread-safe observer pattern. What will be printed after executing the sequence of method calls shown below?

Consider the following Python code implementing a thread-safe observer pattern. What will be printed after executing the sequence of method calls shown below?

import threading

class Observer:
    def __init__(self, id):
        self.id = id
    def notify(self, event, data):
        print(f'Observer {self.id} got {event} with {data}')

class EventManager:
    def __init__(self):
        self.lock = threading.Lock()
        self.subscribers = {}
    def subscribe(self, observer, event):
        with self.lock:
            self.subscribers.setdefault(event, set()).add(observer)
    def publish(self, event, data):
        with self.lock:
            observers = list(self.subscribers.get(event, []))
        for obs in observers:
            obs.notify(event, data)

mgr = EventManager()
obs1 = Observer(1)
obs2 = Observer(2)
mgr.subscribe(obs1, 'update')
mgr.subscribe(obs2, 'update')
mgr.publish('update', 'version 1')
mgr.publish('delete', 'file.txt')