update location model

billard/models.py

@@ -1,5 +1,6 @@
 import uuid
 from django.db import models
+from django.contrib.auth.models import User
 
 
 class LocationData(models.Model):
@@ -18,6 +19,7 @@ class LocationData(models.Model):
 
 
 class Location(models.Model):
+    users = models.ManyToManyField(User, related_name='locations')
     code = models.CharField(max_length=16, unique=True)
     name = models.CharField(max_length=64, unique=True)
     street = models.CharField(max_length=64, blank=True, null=True)