diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 736166785fe6b2930deefc33399cb05f63dc0752..d8fe3c6ae4f5d9cb89dc31bc65d677e806169ee2 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: python:3.9
+image: python:3.11
 
 #services:
 #  - postgres:13
diff --git a/src/homework/serializers.py b/src/homework/serializers.py
index 498e4e01ea0eb0ad0d1aed1ba737a7dcbd40daac..0e0a6c3fa5c39aab4f1948e4532265540becfb97 100755
--- a/src/homework/serializers.py
+++ b/src/homework/serializers.py
@@ -1,6 +1,7 @@
 from rest_framework import serializers
 from django.utils import timezone
 from . import models
+from account.models import Profile
 from common.email import homework_corrected, new_homework
 
 
diff --git a/src/images/models.py b/src/images/models.py
index cab2442d4eefa7e8d5200145ab567d911d12bffb..c9495d3e1820fe0fdae7c29f2856f5d5eed0e3f9 100644
--- a/src/images/models.py
+++ b/src/images/models.py
@@ -12,6 +12,7 @@ class Image(models.Model):
     def __str__(self):
         return str(self.id)
 
+
 # Deletes file from filesystem when File object is deleted.
 @receiver(models.signals.post_delete, sender=Image)
 def auto_delete_image_on_delete(sender, instance, **kwargs):
diff --git a/src/mentors/models.py b/src/mentors/models.py
index b641319bcfe6aaf07c8754ef13850c4c9e53491c..1fa64ea8b2614abb69bd571cf62e73d1bf38483d 100644
--- a/src/mentors/models.py
+++ b/src/mentors/models.py
@@ -14,6 +14,7 @@ class Mentor(models.Model):
     def __str__(self):
         return self.name
 
+
 # Deletes file from filesystem when File object is deleted.
 @receiver(models.signals.post_delete, sender=Mentor)
 def auto_delete_image_on_delete(sender, instance, **kwargs):