Refactor test utilities and enhance ASGI settings

- Cleaned up and standardized assertions in ApiTestMixin for API response validation.
- Updated ASGI settings to use os.environ for setting the DJANGO_SETTINGS_MODULE.
- Removed unused imports and improved formatting in settings.py.
- Refactored URL patterns in urls.py for better readability and organization.
- Enhanced view functions in views.py for consistency and clarity.
- Added .flake8 configuration for linting and style enforcement.
- Introduced type stubs for django-environ to improve type checking with Pylance.

parks/signals.py

@@ -1,34 +1,33 @@
 from django.db.models.signals import post_save, post_delete
 from django.dispatch import receiver
-from django.db.models import Count, Q
+from django.db.models import Q
 
 from rides.models import Ride
 from .models import Park
 
+
 def update_park_ride_counts(park):
     """Update ride_count and coaster_count for a park"""
-    operating_rides = Q(status='OPERATING')
-    
+    operating_rides = Q(status="OPERATING")
+
     # Count total operating rides
     ride_count = park.rides.filter(operating_rides).count()
-    
+
     # Count total operating roller coasters
-    coaster_count = park.rides.filter(
-        operating_rides,
-        category='RC'
-    ).count()
-    
+    coaster_count = park.rides.filter(operating_rides, category="RC").count()
+
     # Update park counts
     Park.objects.filter(id=park.id).update(
-        ride_count=ride_count,
-        coaster_count=coaster_count
+        ride_count=ride_count, coaster_count=coaster_count
     )
 
+
 @receiver(post_save, sender=Ride)
 def ride_saved(sender, instance, **kwargs):
     """Update park counts when a ride is saved"""
     update_park_ride_counts(instance.park)
 
+
 @receiver(post_delete, sender=Ride)
 def ride_deleted(sender, instance, **kwargs):
     """Update park counts when a ride is deleted"""