models.py

from django.db import models
from django.contrib.staticfiles.storage import staticfiles_storage


DEFAULT_IMAGE = 'img/default.svg'


class Place(models.Model):
    name = models.CharField(max_length=50, unique=True)
    image = models.ImageField(upload_to="places/", blank=True, null=True)
    
    def __str__(self):
        return self.name
    
    def get_image_url(self):
        if not self.image:
            return staticfiles_storage.url(DEFAULT_IMAGE)
        
        return self.image.url