Why my django signals not working for User model?

I want to implement django signals on User model for create user profile. I want to create user profile when any user will be created. here is my code for create user profile though signals:

from django.contrib.auth.models import User


@receiver(post_save, sender=User)
def user_is_created_or_save(sender,instance,created,**kwargs):
         user = instance.user
         first_name = instance.first_name
         last_name = instance.last_name
         if created:
            UserProfile.objects.create(user=user)

I am not understanding why user profile not creating when I am creating any user. Assume I created an user from django admin panel so it should be create an profile for user but it’s not creating any user profile.

Why do you use this method?