diff --git a/src/account/migrations/0001_initial.py b/src/account/migrations/0001_initial.py
index 8550f16222d06151f89e7dbf62fb44cc7233e753..8a477bdaf4bec82fb83708e8b1e1d314a1318004 100644
--- a/src/account/migrations/0001_initial.py
+++ b/src/account/migrations/0001_initial.py
@@ -17,7 +17,8 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Deadline',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('deadline', models.DateTimeField(null=True)),
             ],
             options={
@@ -27,14 +28,17 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='GroupChoice',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('choice', models.CharField(choices=[('DT', 'DevTeam'), ('NET', 'NeTeam'), ('ST', 'SecurITeam'), ('SYS', 'SysAdmin'), ('HAT', 'HallgatĂłi TudĂĄsbĂĄzis'), ('N', 'None')], default='N', max_length=10, unique=True)),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
+                ('choice', models.CharField(choices=[('DT', 'DevTeam'), ('NET', 'NeTeam'), ('ST', 'SecurITeam'), (
+                    'SYS', 'SysAdmin'), ('HAT', 'HallgatĂłi TudĂĄsbĂĄzis'), ('N', 'None')], default='N', max_length=10, unique=True)),
             ],
         ),
         migrations.CreateModel(
             name='Profile',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('join_date', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
                 ('motivation_about', models.TextField(blank=True, default='')),
@@ -42,9 +46,12 @@ class Migration(migrations.Migration):
                 ('motivation_exercise', models.TextField(blank=True, default='')),
                 ('nick', models.CharField(blank=True, default='', max_length=15)),
                 ('signed', models.BooleanField(default=False)),
-                ('role', models.CharField(choices=[('Staff', 'Staff'), ('Applicant', 'Applicant'), ('Student', 'Student')], default='Applicant', max_length=10)),
-                ('groups', models.ManyToManyField(blank=True, related_name='profiles', to='account.GroupChoice')),
-                ('user', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='profile', to=settings.AUTH_USER_MODEL)),
+                ('role', models.CharField(choices=[('Staff', 'Staff'), ('Applicant', 'Applicant'), (
+                    'Student', 'Student')], default='Applicant', max_length=10)),
+                ('groups', models.ManyToManyField(blank=True,
+                                                  related_name='profiles', to='account.GroupChoice')),
+                ('user', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE,
+                                              related_name='profile', to=settings.AUTH_USER_MODEL)),
             ],
         ),
     ]
diff --git a/src/account/migrations/0002_auto_20190122_1341.py b/src/account/migrations/0002_auto_20190122_1341.py
index e9ee7b662af95a01f09815050e8650ab04603b30..bb010a2b47f77be10ce101b4ad90d4d3fe403341 100644
--- a/src/account/migrations/0002_auto_20190122_1341.py
+++ b/src/account/migrations/0002_auto_20190122_1341.py
@@ -13,6 +13,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='profile',
             name='role',
-            field=models.CharField(choices=[('Staff', 'Staff'), ('Applicant', 'Applicant'), ('Student', 'Student'), ('Denied', 'Denied')], default='Applicant', max_length=10),
+            field=models.CharField(choices=[('Staff', 'Staff'), ('Applicant', 'Applicant'), (
+                'Student', 'Student'), ('Denied', 'Denied')], default='Applicant', max_length=10),
         ),
     ]
diff --git a/src/account/migrations/0003_auto_20200202_1541.py b/src/account/migrations/0003_auto_20200202_1541.py
index dcc6f8b6da31a12762cd0a615df8de9f40a2f12c..fdfda988e7024d3f03516a0594b5c9d9ffaa1cc6 100644
--- a/src/account/migrations/0003_auto_20200202_1541.py
+++ b/src/account/migrations/0003_auto_20200202_1541.py
@@ -18,6 +18,7 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='profile',
             name='image',
-            field=models.ImageField(blank=True, null=True, upload_to='accounts/images/'),
+            field=models.ImageField(
+                blank=True, null=True, upload_to='accounts/images/'),
         ),
     ]
diff --git a/src/account/models.py b/src/account/models.py
index 21bfbfac2c7a73b0b4e0b3d3c5fee6734dd46c45..40a38470f6478f44b733c1f7c1b25f606db00141 100644
--- a/src/account/models.py
+++ b/src/account/models.py
@@ -2,7 +2,7 @@ from django.db import models
 from django.contrib.auth.models import User
 from solo.models import SingletonModel
 from django.db.models import Sum
-from django.db.models.functions import Coalesce   
+
 
 class GroupChoice(models.Model):
     TEAMS = (
@@ -46,14 +46,17 @@ class Profile(models.Model):
     groups = models.ManyToManyField(
         GroupChoice, related_name='profiles', blank=True)
     role = models.CharField(max_length=10, choices=ROLES, default='Applicant')
-    
+
     @property
     def events_visited(self):
         return self.events_visitor.all().count()
-    
+
     @property
     def homework_bits(self):
-        return self.solution.filter(accepted=True).values('task__bits').aggregate(total_bits=Sum('task__bits')).get('total_bits')
+        return self.solution.filter(accepted=True) \
+            .values('task__bits') \
+            .aggregate(total_bits=Sum('task__bits')) \
+            .get('total_bits')
 
     @property
     def full_name(self):
diff --git a/src/account/resources.py b/src/account/resources.py
index 4682f638b07cadfff0e0d216c394ce466d980866..1217cad331af7ec6fc291ce0417dc2a020284167 100644
--- a/src/account/resources.py
+++ b/src/account/resources.py
@@ -5,7 +5,8 @@ from . import models
 class SignUpResource(resources.ModelResource):
     groups = fields.Field(
         attribute='groups',
-        widget=widgets.ManyToManyWidget(model=models.GroupChoice, separator=' ,', field='choice'),
+        widget=widgets.ManyToManyWidget(
+            model=models.GroupChoice, separator=' ,', field='choice'),
     )
 
     class Meta:
diff --git a/src/account/serializers.py b/src/account/serializers.py
index 01ba66c76f2d4c974b929fb965388bc62f0b710d..ae7b5bafeef15c9dca8de074aecacc5a5f9eda5e 100644
--- a/src/account/serializers.py
+++ b/src/account/serializers.py
@@ -9,6 +9,7 @@ class ChoiceSerializer(serializers.ModelSerializer):
         model = models.GroupChoice
         fields = ('choice', 'profile')
 
+
 class ProfileSerializer_User(serializers.ModelSerializer):
     groups = serializers.SlugRelatedField(
         many=True,
@@ -66,7 +67,7 @@ class ProfileSerializer_User(serializers.ModelSerializer):
 
     def get_full_name(self, obj):
         return obj.full_name
-    
+
     def get_bits(self, obj):
         if obj.homework_bits is None:
             return obj.events_visited
diff --git a/src/account/views.py b/src/account/views.py
index 9321defcd2c0031f9746656a2fdd5269e08ebc90..4f88c5140b7e7c19be08f485d18798be2c627974 100644
--- a/src/account/views.py
+++ b/src/account/views.py
@@ -31,7 +31,7 @@ class ProfileViewSet(viewsets.ModelViewSet):
     def me(self, request):
         serializer = self.serializer_class(request.user.profile)
         return Response(serializer.data)
-    
+
     @action(detail=False)
     def deadline(self, request):
         deadline = models.Deadline.get_solo()
diff --git a/src/common/email.py b/src/common/email.py
index 45b8705f994cea140f6746831d916630364d0c0e..804231fc0ecd560e15b84e9bc20fac63943c2c40 100644
--- a/src/common/email.py
+++ b/src/common/email.py
@@ -36,7 +36,8 @@ def new_homework(user, deadline):
     deadline = deadline.strftime('%Y-%m-%d %H:%M')
     subject = "Új házifeladat"
     message = read_email('new_homework.txt')
-    message = str.format(message % {'name': user.get_full_name(), 'link': link, 'deadline': deadline})
+    message = str.format(
+        message % {'name': user.get_full_name(), 'link': link, 'deadline': deadline})
     send_mail(subject, message, sender_email, [user.email, ])
 
 
@@ -47,5 +48,6 @@ def homework_corrected(user, title, accepted):
     else:
         status = 'HibĂĄs'
     message = read_email('homework_corrected.txt')
-    message = str.format(message % {'name': user.get_full_name(), 'link': link, 'status': status, 'title': title})
+    message = str.format(message % {'name': user.get_full_name(
+    ), 'link': link, 'status': status, 'title': title})
     send_mail(subject, message, sender_email, [user.email, ])
diff --git a/src/common/permissions.py b/src/common/permissions.py
index 7d2384c7bf9186939272c68ac9d5f61dbfe58e72..71019190dc24d58c05180291c99b3d4f83ed1fcd 100644
--- a/src/common/permissions.py
+++ b/src/common/permissions.py
@@ -5,13 +5,13 @@ from rest_framework.permissions import SAFE_METHODS
 class IsStaffOrReadOnly(BasePermission):
     def has_permission(self, request, view):
         return request.method in SAFE_METHODS or\
-               (request.user.is_authenticated and request.user.profile.role == 'Staff')
+            (request.user.is_authenticated and request.user.profile.role == 'Staff')
 
 
 class IsStaffOrReadOnlyForAuthenticated(BasePermission):
     def has_permission(self, request, view):
         return request.user.is_authenticated and\
-               (request.method in SAFE_METHODS or request.user.profile.role == 'Staff')
+            (request.method in SAFE_METHODS or request.user.profile.role == 'Staff')
 
 
 class IsStaffUser(BasePermission):
@@ -27,4 +27,5 @@ class IsSafeOrPatch(BasePermission):
 class IsStaffOrStudent(BasePermission):
     def has_permission(self, request, view):
         return request.user.is_authenticated and\
-               (request.user.profile.role == 'Staff' or request.user.profile.role == 'Student')
+            (request.user.profile.role ==
+             'Staff' or request.user.profile.role == 'Student')
diff --git a/src/document/migrations/0001_initial.py b/src/document/migrations/0001_initial.py
index 4348982492986d644aa5a1c31dd744a4df499438..7b6f640281ba41f95d5d03c76db5308c453ec343 100644
--- a/src/document/migrations/0001_initial.py
+++ b/src/document/migrations/0001_initial.py
@@ -21,13 +21,17 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Document',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('uploaded_at', models.DateTimeField(auto_now_add=True)),
                 ('name', models.CharField(blank=True, default='', max_length=150)),
                 ('description', models.TextField(blank=True, default='')),
-                ('file', models.FileField(blank=True, null=True, upload_to=document.models.document_file_name, validators=[django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)])),
-                ('solution', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='files', to='homework.Solution')),
-                ('uploaded_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='documents', to='account.Profile')),
+                ('file', models.FileField(blank=True, null=True, upload_to=document.models.document_file_name, validators=[
+                 django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)])),
+                ('solution', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE,
+                                               related_name='files', to='homework.Solution')),
+                ('uploaded_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                                  on_delete=django.db.models.deletion.DO_NOTHING, related_name='documents', to='account.Profile')),
             ],
         ),
     ]
diff --git a/src/document/migrations/0002_auto_20190121_1332.py b/src/document/migrations/0002_auto_20190121_1332.py
index 5cf755b92259e186c711bd5be422791f17294858..3e91175e44049fa5517660e8ef19e1b32e3c5c0b 100644
--- a/src/document/migrations/0002_auto_20190121_1332.py
+++ b/src/document/migrations/0002_auto_20190121_1332.py
@@ -15,6 +15,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='document',
             name='file',
-            field=models.FileField(blank=True, default='', upload_to='', validators=[django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
+            field=models.FileField(blank=True, default='', upload_to='', validators=[django.core.validators.FileExtensionValidator(
+                ['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
         ),
     ]
diff --git a/src/document/migrations/0003_auto_20190121_1335.py b/src/document/migrations/0003_auto_20190121_1335.py
index fa4d1c22ae825d615e093126a69d4a0a76132ad0..fe059ec31970f9fb4186389c5a021ad771e20c7a 100644
--- a/src/document/migrations/0003_auto_20190121_1335.py
+++ b/src/document/migrations/0003_auto_20190121_1335.py
@@ -15,6 +15,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='document',
             name='file',
-            field=models.FileField(blank=True, upload_to='', validators=[django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
+            field=models.FileField(blank=True, upload_to='', validators=[django.core.validators.FileExtensionValidator(
+                ['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
         ),
     ]
diff --git a/src/document/migrations/0004_auto_20190123_1812.py b/src/document/migrations/0004_auto_20190123_1812.py
index 9eb42c6664d6d3fe22abb6ec091b7ea965643db5..95a9a1c5acf4b94783ffc434dc6b10c52c2cb560 100644
--- a/src/document/migrations/0004_auto_20190123_1812.py
+++ b/src/document/migrations/0004_auto_20190123_1812.py
@@ -14,6 +14,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='document',
             name='solution',
-            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='files', to='homework.Solution'),
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE, related_name='files', to='homework.Solution'),
         ),
     ]
diff --git a/src/document/migrations/0005_auto_20190129_1438.py b/src/document/migrations/0005_auto_20190129_1438.py
index 5c207c4a9776a2776d3d1b5da9d0473d2a283175..da8acfc706738e46cd96842231f34d7510febf0d 100644
--- a/src/document/migrations/0005_auto_20190129_1438.py
+++ b/src/document/migrations/0005_auto_20190129_1438.py
@@ -15,7 +15,8 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='document',
             name='file',
-            field=models.FileField(blank=True, null=True, upload_to='', validators=[django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
+            field=models.FileField(blank=True, null=True, upload_to='', validators=[django.core.validators.FileExtensionValidator(
+                ['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
         ),
         migrations.AlterField(
             model_name='document',
diff --git a/src/document/migrations/0006_auto_20200203_0016.py b/src/document/migrations/0006_auto_20200203_0016.py
index 4fe709a5402e848967cacf18078031d5e3386a46..a8e13ced35131bd48da645e5f838e32128d66f90 100644
--- a/src/document/migrations/0006_auto_20200203_0016.py
+++ b/src/document/migrations/0006_auto_20200203_0016.py
@@ -16,6 +16,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='document',
             name='file',
-            field=models.FileField(blank=True, null=True, upload_to=document.models.document_file_name, validators=[django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
+            field=models.FileField(blank=True, null=True, upload_to=document.models.document_file_name, validators=[
+                                   django.core.validators.FileExtensionValidator(['png', 'jpeg', 'jpg', 'zip']), common.validators.FileSizeValidator(size_limit=52428800)]),
         ),
     ]
diff --git a/src/document/models.py b/src/document/models.py
index efa6d39b9c825c731779e07bb9185517ce007adc..11eeb96fd9ab4990169d5e5b504e99175a9a6395 100644
--- a/src/document/models.py
+++ b/src/document/models.py
@@ -43,7 +43,8 @@ class Document(models.Model):
         null=True,
         upload_to=document_file_name
     )
-    solution = models.ForeignKey(Solution, related_name='files', on_delete=models.CASCADE)
+    solution = models.ForeignKey(
+        Solution, related_name='files', on_delete=models.CASCADE)
 
     def __str__(self):
         return self.name
diff --git a/src/groups/migrations/0001_initial.py b/src/groups/migrations/0001_initial.py
index a0a4157f9ecc22f02146c2f662ecd11af1b5e25f..643e9bace651b115a74ee0ce5c4dcbc9157b6b82 100644
--- a/src/groups/migrations/0001_initial.py
+++ b/src/groups/migrations/0001_initial.py
@@ -14,7 +14,8 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Group',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('name', models.CharField(blank=True, default='', max_length=50)),
                 ('description', models.TextField(blank=True, default='')),
             ],
diff --git a/src/groups/models.py b/src/groups/models.py
index 88a35cf5ebf1ed80ea968b1e9259dee34df19354..2953fdc811b6e9a837cd4e4eb6b1cf8f4f72f9bd 100644
--- a/src/groups/models.py
+++ b/src/groups/models.py
@@ -1,9 +1,11 @@
 from django.db import models
 
 # KSZK groups, like Devteam, Sysadmin, ...
+
+
 class Group(models.Model):
     name = models.CharField(max_length=50, blank=True, default='')
     description = models.TextField(blank=True, default='')
-    
+
     def __str__(self):
-        return self.name
\ No newline at end of file
+        return self.name
diff --git a/src/groups/serializers.py b/src/groups/serializers.py
index 0baeea0970993b58d9c5bc872320d1ad57c38f5a..2f14fa78374ea5983b9ec38f05d4f50be82b760e 100644
--- a/src/groups/serializers.py
+++ b/src/groups/serializers.py
@@ -14,5 +14,3 @@ class GroupSerializer(serializers.ModelSerializer):
             'name',
             'description',
         )
-
-
diff --git a/src/groups/tests.py b/src/groups/tests.py
index 7ce503c2dd97ba78597f6ff6e4393132753573f6..a79ca8be565f44aacce95bad20c1ee34d175ed20 100644
--- a/src/groups/tests.py
+++ b/src/groups/tests.py
@@ -1,3 +1,3 @@
-from django.test import TestCase
+# from django.test import TestCase
 
 # Create your tests here.
diff --git a/src/groups/views.py b/src/groups/views.py
index e22f113ca575f94d0f38061b8c1dd2de4442c34b..2149906966c10423777d5da772f3402579e89904 100644
--- a/src/groups/views.py
+++ b/src/groups/views.py
@@ -3,7 +3,7 @@ from rest_framework import viewsets
 from . import serializers
 from . import models
 
+
 class GroupsViewSet(viewsets.ReadOnlyModelViewSet):
     serializer_class = serializers.GroupSerializer
     queryset = models.Group.objects.all()
-    
\ No newline at end of file
diff --git a/src/homework/migrations/0001_initial.py b/src/homework/migrations/0001_initial.py
index 13125342ce3865c45e5e8304a5353c3b5837e371..d41fc713789e4f4d5a5bcabbe20854da9b411b5c 100644
--- a/src/homework/migrations/0001_initial.py
+++ b/src/homework/migrations/0001_initial.py
@@ -17,30 +17,35 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Solution',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
                 ('note', models.TextField(blank=True, default='')),
                 ('accepted', models.BooleanField()),
                 ('corrected', models.BooleanField()),
-                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='solution', to='account.Profile')),
+                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                                 on_delete=django.db.models.deletion.DO_NOTHING, related_name='solution', to='account.Profile')),
             ],
         ),
         migrations.CreateModel(
             name='Task',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
                 ('title', models.CharField(max_length=150)),
                 ('text', models.TextField()),
                 ('deadline', models.DateTimeField()),
-                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='tasks', to='account.Profile')),
+                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                                 on_delete=django.db.models.deletion.DO_NOTHING, related_name='tasks', to='account.Profile')),
             ],
         ),
         migrations.AddField(
             model_name='solution',
             name='task',
-            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='solutions', to='homework.Task'),
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE, related_name='solutions', to='homework.Task'),
         ),
     ]
diff --git a/src/homework/models.py b/src/homework/models.py
index 6bc36ceb5a05d25dace35ca2caf3f765df62b020..75fddd9ea4c46938f630924f05044217a3489429 100755
--- a/src/homework/models.py
+++ b/src/homework/models.py
@@ -22,7 +22,8 @@ class Task(models.Model):
 
 
 class Solution(models.Model):
-    task = models.ForeignKey(Task, related_name='solutions', on_delete=models.CASCADE)
+    task = models.ForeignKey(
+        Task, related_name='solutions', on_delete=models.CASCADE)
     created_by = models.ForeignKey(
         Profile,
         related_name='solution',
diff --git a/src/kszkepzes/settings/local.py b/src/kszkepzes/settings/local.py
index 53eb49a1bd60f3f66631867f420381d3070b85a1..caa2719d4630ba660fb7e1709250b5530173749b 100644
--- a/src/kszkepzes/settings/local.py
+++ b/src/kszkepzes/settings/local.py
@@ -1,6 +1,6 @@
 from .base import *
 
-SESSION_COOKIE_SECURE=False
+SESSION_COOKIE_SECURE = False
 EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
 EMAIL_HOST = 'smtp.gmail.com'
 EMAIL_USE_TLS = True
diff --git a/src/kszkepzes/urls.py b/src/kszkepzes/urls.py
index 36b2b6bb87de5468f80a403ffbacc6fd3cd84846..0760d77eda95fb1a1ac2a54f9de0669a0ae0dfb4 100644
--- a/src/kszkepzes/urls.py
+++ b/src/kszkepzes/urls.py
@@ -22,9 +22,12 @@ schema_view = get_schema_view(
 )
 
 urlpatterns = [
-    url(r'^api/v1/swagger(?P<format>\.json|\.yaml)$', schema_view.without_ui(cache_timeout=0), name='schema-json'),
-    url(r'^api/v1/swagger/$', schema_view.with_ui('swagger', cache_timeout=0), name='schema-swagger-ui'),
-    url(r'^api/v1/redoc/$', schema_view.with_ui('redoc', cache_timeout=0), name='schema-redoc'),
+    url(r'^api/v1/swagger(?P<format>\.json|\.yaml)$',
+        schema_view.without_ui(cache_timeout=0), name='schema-json'),
+    url(r'^api/v1/swagger/$', schema_view.with_ui('swagger',
+                                                  cache_timeout=0), name='schema-swagger-ui'),
+    url(r'^api/v1/redoc/$', schema_view.with_ui('redoc',
+                                                cache_timeout=0), name='schema-redoc'),
     url(r'^admin/', admin.site.urls),
     url(r'^api/v1/', include('social_django.urls', namespace='social')),
     url(r'^api/v1/homework/', include('homework.urls')),
@@ -38,4 +41,5 @@ urlpatterns = [
 ]
 
 if settings.DEBUG:
-    urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
+    urlpatterns += static(settings.MEDIA_URL,
+                          document_root=settings.MEDIA_ROOT)
diff --git a/src/kszkepzes/wsgi.py b/src/kszkepzes/wsgi.py
index 12023b6a78e7c9bbb5cc7e48d9d4f63b9eba7b3e..f29c7593000fed09e6a5a94b4c631462fb71bc73 100644
--- a/src/kszkepzes/wsgi.py
+++ b/src/kszkepzes/wsgi.py
@@ -11,6 +11,7 @@ import os
 
 from django.core.wsgi import get_wsgi_application
 
-os.environ.setdefault("DJANGO_SETTINGS_MODULE", "kszkepzes.settings.production")
+os.environ.setdefault("DJANGO_SETTINGS_MODULE",
+                      "kszkepzes.settings.production")
 
 application = get_wsgi_application()
diff --git a/src/mentors/migrations/0001_initial.py b/src/mentors/migrations/0001_initial.py
index ef3982a1810cc7376a73a0356ec537cef5bb1ea4..782fbdc071f8a8ce33a4cb104fa1a87113eed014 100644
--- a/src/mentors/migrations/0001_initial.py
+++ b/src/mentors/migrations/0001_initial.py
@@ -17,12 +17,15 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Mentor',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('name', models.CharField(max_length=200)),
                 ('text', models.TextField()),
-                ('image', models.ImageField(blank=True, null=True, upload_to='mentors/images/')),
+                ('image', models.ImageField(blank=True,
+                                            null=True, upload_to='mentors/images/')),
                 ('email', models.EmailField(max_length=254)),
-                ('mentor', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='mentor', to='account.Profile')),
+                ('mentor', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                             on_delete=django.db.models.deletion.DO_NOTHING, related_name='mentor', to='account.Profile')),
             ],
         ),
     ]
diff --git a/src/mentors/models.py b/src/mentors/models.py
index 75e6470415d71a2afe41fde5b6b6f1fe5a0d88c5..59b9a720ba88eb81223696f7d7ff982541889230 100644
--- a/src/mentors/models.py
+++ b/src/mentors/models.py
@@ -12,7 +12,8 @@ class Mentor(models.Model):
     )
     name = models.CharField(null=False, max_length=200)
     text = models.TextField()
-    image = models.ImageField(upload_to='mentors/images/', null=True, blank=True)
+    image = models.ImageField(
+        upload_to='mentors/images/', null=True, blank=True)
     email = models.EmailField()
 
     def __str__(self):
diff --git a/src/mentors/serializers.py b/src/mentors/serializers.py
index c5ef6d7498b0e30b928edbbafd7b7936b228c3bf..a32b29c48d106482bd6559ed4ead9cffec11c99b 100644
--- a/src/mentors/serializers.py
+++ b/src/mentors/serializers.py
@@ -1,6 +1,5 @@
 from mentors.models import Mentor
 from rest_framework import serializers
-from common.serializers import CurrentUserProfileDefault
 
 
 class MentorSerializer(serializers.ModelSerializer):
diff --git a/src/news/migrations/0001_initial.py b/src/news/migrations/0001_initial.py
index a8f40ce6d982860cc36fa0d335132bf70b770d9e..844a7e255bb247a53191d9ce0965ffe77c31fda3 100644
--- a/src/news/migrations/0001_initial.py
+++ b/src/news/migrations/0001_initial.py
@@ -17,13 +17,16 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Article',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('title', models.CharField(max_length=200)),
                 ('text', models.TextField()),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
-                ('author', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='author', to='account.Profile')),
-                ('updated_by', models.ForeignKey(on_delete=django.db.models.deletion.DO_NOTHING, related_name='updater', to='account.Profile')),
+                ('author', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                             on_delete=django.db.models.deletion.DO_NOTHING, related_name='author', to='account.Profile')),
+                ('updated_by', models.ForeignKey(on_delete=django.db.models.deletion.DO_NOTHING,
+                                                 related_name='updater', to='account.Profile')),
             ],
         ),
     ]
diff --git a/src/news/migrations/0002_auto_20200202_1541.py b/src/news/migrations/0002_auto_20200202_1541.py
index 07d6f60484beec02c0a89fd61a682a51bc86e467..ecd6a503a7f89050469a3d651eeacd1316b78867 100644
--- a/src/news/migrations/0002_auto_20200202_1541.py
+++ b/src/news/migrations/0002_auto_20200202_1541.py
@@ -15,6 +15,7 @@ class Migration(migrations.Migration):
         migrations.AlterField(
             model_name='article',
             name='updated_by',
-            field=models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='updater', to='account.Profile'),
+            field=models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                    on_delete=django.db.models.deletion.DO_NOTHING, related_name='updater', to='account.Profile'),
         ),
     ]
diff --git a/src/news/serializers.py b/src/news/serializers.py
index c6a84629f0fc62ba21cfd864effe382af2e63ba9..7d967b59bde22839708b919f0796cfc39d716d9c 100644
--- a/src/news/serializers.py
+++ b/src/news/serializers.py
@@ -1,6 +1,5 @@
 from news.models import Article
 from rest_framework import serializers
-from common.serializers import CurrentUserProfileDefault
 
 
 class ArticleSerializer(serializers.ModelSerializer):
diff --git a/src/stats/admin.py b/src/stats/admin.py
index fb841605335f9cd12025ed91abe5361dc7f806f5..6c3f3b784e18268a87cbc7f48dd87392cb54c746 100644
--- a/src/stats/admin.py
+++ b/src/stats/admin.py
@@ -15,7 +15,8 @@ class EventAdmin(ExportMixin, admin.ModelAdmin):
 
 @admin.register(models.Note)
 class NoteAdmin(ExportMixin, admin.ModelAdmin):
-    list_display = ('profile', 'note', 'event', 'created_by', 'created_at', 'updated_at')
+    list_display = ('profile', 'note', 'event',
+                    'created_by', 'created_at', 'updated_at')
     list_filter = ('profile', 'created_by', 'event')
     search_fields = ('event__name', 'note')
     resource_class = resources.NoteResource
diff --git a/src/stats/migrations/0001_initial.py b/src/stats/migrations/0001_initial.py
index b6e989e8f6f784a782bf6ef238584160ca141329..2bc6a35d52517eeec7687ce2bf10da4ffa70b81c 100644
--- a/src/stats/migrations/0001_initial.py
+++ b/src/stats/migrations/0001_initial.py
@@ -17,25 +17,32 @@ class Migration(migrations.Migration):
         migrations.CreateModel(
             name='Event',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('name', models.CharField(max_length=255)),
                 ('date', models.DateTimeField()),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
-                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='created_event', to='account.Profile')),
-                ('visitors', models.ManyToManyField(blank=True, related_name='events', to='account.Profile')),
+                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                                 on_delete=django.db.models.deletion.DO_NOTHING, related_name='created_event', to='account.Profile')),
+                ('visitors', models.ManyToManyField(blank=True,
+                                                    related_name='events', to='account.Profile')),
             ],
         ),
         migrations.CreateModel(
             name='Note',
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('id', models.AutoField(auto_created=True,
+                                        primary_key=True, serialize=False, verbose_name='ID')),
                 ('note', models.TextField()),
                 ('created_at', models.DateTimeField(auto_now_add=True)),
                 ('updated_at', models.DateTimeField(auto_now=True)),
-                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile, on_delete=django.db.models.deletion.DO_NOTHING, related_name='created_notes', to='account.Profile')),
-                ('event', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='notes', to='stats.Event')),
-                ('profile', models.ForeignKey(blank=True, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='notes', to='account.Profile')),
+                ('created_by', models.ForeignKey(default=common.middleware.CurrentUserMiddleware.get_current_user_profile,
+                                                 on_delete=django.db.models.deletion.DO_NOTHING, related_name='created_notes', to='account.Profile')),
+                ('event', models.ForeignKey(blank=True, null=True,
+                                            on_delete=django.db.models.deletion.CASCADE, related_name='notes', to='stats.Event')),
+                ('profile', models.ForeignKey(blank=True, null=True,
+                                              on_delete=django.db.models.deletion.CASCADE, related_name='notes', to='account.Profile')),
             ],
         ),
     ]
diff --git a/src/stats/migrations/0003_auto_20190122_1449.py b/src/stats/migrations/0003_auto_20190122_1449.py
index a3689e8ee847704324f3821df0508d6b89ffbb0d..264620d76494437db53a3fd8629dc4aae72552eb 100644
--- a/src/stats/migrations/0003_auto_20190122_1449.py
+++ b/src/stats/migrations/0003_auto_20190122_1449.py
@@ -14,11 +14,13 @@ class Migration(migrations.Migration):
         migrations.AddField(
             model_name='event',
             name='absent',
-            field=models.ManyToManyField(blank=True, related_name='events_absent', to='account.Profile'),
+            field=models.ManyToManyField(
+                blank=True, related_name='events_absent', to='account.Profile'),
         ),
         migrations.AlterField(
             model_name='event',
             name='visitors',
-            field=models.ManyToManyField(blank=True, related_name='events_visitor', to='account.Profile'),
+            field=models.ManyToManyField(
+                blank=True, related_name='events_visitor', to='account.Profile'),
         ),
     ]
diff --git a/src/stats/models.py b/src/stats/models.py
index be958204fba61174220ddc988100c21405f44241..762173fad5b281f05295dac8cb8b2268defe33c2 100644
--- a/src/stats/models.py
+++ b/src/stats/models.py
@@ -31,8 +31,10 @@ class Event(models.Model):
 
 
 class Note(models.Model):
-    event = models.ForeignKey(Event, related_name='notes', on_delete=models.CASCADE, blank=True, null=True)
-    profile = models.ForeignKey(Profile, related_name='notes', on_delete=models.CASCADE, blank=True, null=True)
+    event = models.ForeignKey(
+        Event, related_name='notes', on_delete=models.CASCADE, blank=True, null=True)
+    profile = models.ForeignKey(
+        Profile, related_name='notes', on_delete=models.CASCADE, blank=True, null=True)
     note = models.TextField()
     created_by = models.ForeignKey(
         Profile,
diff --git a/src/stats/resources.py b/src/stats/resources.py
index 712c971ae27eb0f4bebfd30be07eb952d8c5fbb7..b2e284c57094b9ec582900772bf7f007bbdd555e 100644
--- a/src/stats/resources.py
+++ b/src/stats/resources.py
@@ -7,7 +7,8 @@ from . import models
 class EventResource(resources.ModelResource):
     visitors = fields.Field(
         attribute='visitors',
-        widget=widgets.ManyToManyWidget(model=Profile, separator=' ,', field='full_name'),
+        widget=widgets.ManyToManyWidget(
+            model=Profile, separator=' ,', field='full_name'),
     )
 
     class Meta:
diff --git a/src/stats/urls.py b/src/stats/urls.py
index 0e669f8037c98287185212ecbe0c2b43c03bd267..51ed16131f024b07b2401965526d8855ff2cdd35 100644
--- a/src/stats/urls.py
+++ b/src/stats/urls.py
@@ -2,8 +2,10 @@ from rest_framework import routers
 from . import views
 
 router = routers.DefaultRouter()
-router.register(r'staff_events', views.StaffEventViewSet, base_name='staff_events')
-router.register(r'student_events', views.StudentEventViewSet, base_name='student_events')
+router.register(r'staff_events', views.StaffEventViewSet,
+                base_name='staff_events')
+router.register(r'student_events', views.StudentEventViewSet,
+                base_name='student_events')
 router.register(r'notes', views.NoteViewSet, base_name='notes')
 
 urlpatterns = router.urls