Django User model, adding function

Question

I want to add a new function to the default User model of Django for retrieveing a related list of Model type.

Such Foo model:

class Foo(models.Model):
          


        

Answer 1

It's not unusual to substitute user model as it is stated in the docs: https://docs.djangoproject.com/es/1.9/topics/auth/customizing/#substituting-a-custom-user-model, so, having this into account, it is better to get the user model class with the following code:

from django.contrib.auth import get_user_model
UserModel = get_user_model()

Afterwards, you can use this UserModel to add functionality as @Lakshman Prasad suggests: UserModel.add_to_class('get_related_foo_models', get_related_foo_models).

---

In order to get the code executed only once I prefer to use Django application config classes (https://docs.djangoproject.com/es/1.9/ref/applications/), so a full working example will be:

# myapp/__init__.py
default_app_config = 'myapp.apps.MyAppConfig'

# myapp/apps.py
from django.apps import AppConfig
from django.contrib.auth import get_user_model


class MyAppConfig(AppConfig):
    name = 'myapp'
    verbose_name = 'MyApp'

    def ready(self):
        # Add some functions to user model:
        def custom_function(self):
            # Do whatsoever
            pass

        UserModel = get_user_model()
        UserModel.add_to_class('custom_function', custom_function)