Why doesn't memcached save the cache?

Question

Django

Learn caching.
Installed memcached
pip install python-memcached

Enabled caching

CACHES  =  { 
    'default' :  { 
        'BACKEND' :  'django.core.cache.backends.memcached.MemcachedCache' , 
        'LOCATION' :  '127.0.0.1:11211' , 
    } 
}

I connected my context_processors because in the future I want to display information in the template

from django.core.cache import cache
def user_sitebar(request):
    cache.set('my_key', 'hello, world!', 30)
    print(cache.get('my_key'))

The output is always None. There are no errors, but for some reason the value is not read or set. Why?