Declare Budget.memberships generic relation

arkindex/budget/models.py

 import uuid
 
 from django.conf import settings
+from django.contrib.contenttypes.fields import GenericRelation
 from django.core.validators import MinLengthValidator
 from django.db import models
 
@@ -9,6 +10,7 @@ class Budget(models.Model):
     id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     name = models.CharField(max_length=100, validators=[MinLengthValidator(1)])
     total = models.DecimalField(max_digits=12, decimal_places=3, default=0)
+    memberships = GenericRelation("users.Right", "content_id")
 
     def __str__(self) -> str:
         return self.name