Python string formatting: % vs concatenation

Question

I\'m developing an application in which I perform some requests to get an object id. After each one of them, I call a method (get_actor_info()) passing this id

Answer 1

Python 3.6 will introduce yet another option:

ACTOR_CACHE_KEY_PREFIX = 'actor_'

def get_actor_info(actor_id):
    cache_key = f'{ACTOR_CACHE_KEY_PREFIX}{actor_id}'

Performance should be comparable to '{}{}'.format(ACTOR_CACHE_KEY_PREFIX, actor_id), but is arguably more readable.