Added validation for countries, added patch method for profile page, code improvements and small fixes

solution/pulse/countries/views.py

@@ -1,4 +1,5 @@
-from django.db.models import Q
+from django.conf import settings
+from rest_framework.exceptions import ValidationError
 from rest_framework.generics import ListAPIView, RetrieveAPIView
 
 from countries.models import Country
@@ -13,10 +14,17 @@ class CountryListView(ListAPIView):
         regions = self.request.query_params.get("region")
         if regions:
             regions_list = regions.split(",")
-            query = Q()
-            for region in regions_list:
-                query |= Q(region=region)
-            queryset = queryset.filter(query)
+            invalid_regions = [
+                region
+                for region in regions_list
+                if region not in settings.REGIONS
+            ]
+            if invalid_regions:
+                invalid_regions_str = ", ".join(invalid_regions)
+                error_message = f"Invalid region(s): {invalid_regions_str}"
+                raise ValidationError(error_message)
+
+            queryset = queryset.filter(region__in=regions_list)
         return queryset