🚨(pylint) make pylint work and fix issues found

Pylint was not installed and wrongly configured. After making
it work, we fix all the issues found so it can be added to our
CI requirements.

src/backend/core/api/viewsets.py

@@ -1,30 +1,24 @@
 """API endpoints"""
-import io
-import uuid
-from http import HTTPStatus
-
 from django.contrib.postgres.search import TrigramSimilarity
 from django.core.cache import cache
-from django.core.exceptions import ValidationError
 from django.db.models import (
-    CharField,
-    Count,
-    F,
     Func,
     OuterRef,
-    Prefetch,
     Q,
     Subquery,
-    TextField,
     Value,
-    functions,
 )
 
-from rest_framework import decorators, mixins, pagination, response, viewsets
-from rest_framework import permissions as drf_permissions
-from rest_framework.exceptions import ValidationError as DRFValidationError
+from rest_framework import (
+    decorators,
+    exceptions,
+    mixins,
+    pagination,
+    response,
+    viewsets,
+)
 
-from core import enums, models
+from core import models
 
 from . import permissions, serializers
 
@@ -109,6 +103,7 @@ class Pagination(pagination.PageNumberPagination):
     page_size_query_param = "page_size"
 
 
+# pylint: disable=too-many-ancestors
 class ContactViewSet(
     mixins.CreateModelMixin,
     mixins.DestroyModelMixin,
@@ -159,7 +154,6 @@ class ContactViewSet(
         key_base = f"throttle-contact-list-{user.id!s}"
         key_minute = f"{key_base:s}-minute"
         key_hour = f"{key_base:s}-hour"
-        key_day = f"{key_base:s}-day"
 
         try:
             count_minute = cache.incr(key_minute)
@@ -173,14 +167,8 @@ class ContactViewSet(
             cache.set(key_hour, 1, 3600)
             count_hour = 1
 
-        try:
-            count_day = cache.incr(key_day)
-        except ValueError:
-            cache.set(key_day, 1, 86400)
-            count_day = 1
-
-        if count_minute > 20 or count_hour > 150 or count_day > 500:
-            raise drf_exceptions.Throttled()
+        if count_minute > 20 or count_hour > 150:
+            raise exceptions.Throttled()
 
         serializer = self.get_serializer(queryset, many=True)
         return response.Response(serializer.data)
@@ -333,7 +321,7 @@ class TeamAccessViewSet(
 
         # Check if the access being deleted is the last owner access for the team
         if instance.role == "owner" and team.accesses.filter(role="owner").count() == 1:
-            return Response(
+            return response.Response(
                 {"detail": "Cannot delete the last owner access for the team."},
                 status=400,
             )
@@ -355,10 +343,7 @@ class TeamAccessViewSet(
                 instance.role == models.RoleChoices.OWNER
                 and team.accesses.filter(role=models.RoleChoices.OWNER).count() == 1
             ):
-                raise serializers.ValidationError(
-                    {
-                        "role": "Cannot change the role to a non-owner role for the last owner access."
-                    }
-                )
+                message = "Cannot change the role to a non-owner role for the last owner access."
+                raise exceptions.ValidationError({"role": message})
 
         serializer.save()