from django.db.models.signals import post_save
from django.dispatch import receiver


class Profile(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    ...


    @receiver(post_save, sender=User)
    def create_user_profile(sender, instance, created, **kwargs):
        if created:
            Profile.objects.create(user=instance)

    @receiver(post_save, sender=User)
    def save_user_profile(sender, instance, **kwargs):
        instance.profile.save()

    def __str__(self):
        return self.user

from pytils import translit   

class Book(models.Model):
     
   def get_image_path(self, filename):
           path = ''.join(["pictures/",translit.slugify(filename)])
           return path
       ...
     image = models.ImageField(verbose_name='Изображение', upload_to=get_image_path)