Generate unique id for a model field -- regenerate if id exists

generate_unique_id.py

import string
import random

from django.db import models


def generate_random_number(len: int):
    return "".join(
        random.choice(string.ascii_lowercase + string.digits) for _ in range(len)
    )


def generate_unique_id(klass, field, len=6):
    new_field = generate_random_number(len)

    if klass.objects.filter(**{field: new_field}).exists():
        return generate_unique_id(klass, field, len)
    return new_field
    
    
 ############### USAGE #################
 
 
 class MyModel(models.Model):
    ...
    
    def save(self, *args, **kwargs):
        if not self.pk:
            self.my_field = generate_unique_id(MyModel, "my_field")
        super(MyModel, self).save(*args, **kwargs)