diff --git a/src/account/models.py b/src/account/models.py
index 84a4c47a0a06bc9aaa6e5d1407665a608d309c0a..dfea06b79723ac49c2854545ac7616a34c2733ac 100644
--- a/src/account/models.py
+++ b/src/account/models.py
@@ -12,7 +12,11 @@ class GroupChoice(models.Model):
         ('HAT', 'HallgatĂłi TudĂĄsbĂĄzis'),
         ('N', 'None'),
     )
-    choice = models.CharField(max_length=10, choices=TEAMS, default='N', unique=True)
+    choice = models.CharField(
+        max_length=10,
+        choices=TEAMS,
+        default='N',
+        unique=True)
 
     def __str__(self):
         return self.choice
@@ -32,18 +36,20 @@ class Profile(models.Model):
         related_name='profile',
         on_delete=models.CASCADE
     )
-    # TODO: Change the default to json render side
+
     motivation_about = models.TextField(blank=True, default='')
     motivation_profession = models.TextField(blank=True, default='')
     motivation_exercise = models.TextField(blank=True, default='')
     nick = models.CharField(max_length=15, blank=True, default='')
     signed = models.BooleanField(default=False, null=False)
-    groups = models.ManyToManyField(GroupChoice, related_name='profiles', blank=True)
+    groups = models.ManyToManyField(
+        GroupChoice, related_name='profiles', blank=True)
     role = models.CharField(max_length=10, choices=ROLES, default='Applicant')
 
     @property
     def score(self):
-        return  self.events_visitor.all().count()*10 + self.solution.filter(accepted=True).count()*50
+        return self.events_visitor.all().count() * 10 + \
+            self.solution.filter(accepted=True).count() * 50
 
     @property
     def full_name(self):
diff --git a/src/account/serializers.py b/src/account/serializers.py
index 52ce77f49f28a5c06dfb03ecbd629ad6a5015201..0246dd2f544ab1d59b2da84c228f7e659f893c40 100644
--- a/src/account/serializers.py
+++ b/src/account/serializers.py
@@ -11,7 +11,10 @@ class ChoiceSerializer(serializers.ModelSerializer):
 
 
 class ProfileSerializer_User(serializers.ModelSerializer):
-    groups = serializers.SlugRelatedField(many=True, slug_field='choice', queryset=models.GroupChoice.objects.all())
+    groups = serializers.SlugRelatedField(
+        many=True,
+        slug_field='choice',
+        queryset=models.GroupChoice.objects.all())
     updated_at = serializers.DateTimeField(read_only=True)
     full_name = serializers.SerializerMethodField()
 
@@ -36,17 +39,18 @@ class ProfileSerializer_User(serializers.ModelSerializer):
     def validate_updated_at(self, value):
         deadline = models.Deadline.get_solo().deadline
         if deadline is not None and value > deadline:
-            raise serializers.ValidationError("You cannot join after the deadline")
+            raise serializers.ValidationError(
+                "You cannot join after the deadline")
         return value
 
     def validate_role(self, value):
         modifier_role = CurrentUserMiddleware.get_current_user_profile().role
         if value != modifier_role:
-            raise serializers.ValidationError("You don't have permission change role")
+            raise serializers.ValidationError(
+                "You don't have permission change role")
         return value
 
     def validate_signed(self, value):
-        modifier = CurrentUserMiddleware.get_current_user_profile()
         if value is False:
             raise serializers.ValidationError("You cannot join without signed")
         return value
@@ -63,8 +67,12 @@ class ProfileSerializer_User(serializers.ModelSerializer):
     def get_full_name(self, obj):
         return obj.full_name
 
+
 class ProfileSerializer_Staff(serializers.ModelSerializer):
-    groups = serializers.SlugRelatedField(many=True, slug_field='choice', queryset=models.GroupChoice.objects.all())
+    groups = serializers.SlugRelatedField(
+        many=True,
+        slug_field='choice',
+        queryset=models.GroupChoice.objects.all())
     updated_at = serializers.DateTimeField(read_only=True)
     full_name = serializers.SerializerMethodField()
 
@@ -89,7 +97,8 @@ class ProfileSerializer_Staff(serializers.ModelSerializer):
     def validate_updated_at(self, value):
         deadline = models.Deadline.get_solo().deadline
         if deadline is not None and value > deadline:
-            raise serializers.ValidationError("You cannot join after the deadline")
+            raise serializers.ValidationError(
+                "You cannot join after the deadline")
         return value
 
     def validate_role(self, value):
@@ -108,4 +117,4 @@ class ProfileSerializer_Staff(serializers.ModelSerializer):
         return super().update(instance, validated_data)
 
     def get_full_name(self, obj):
-        return obj.full_name
\ No newline at end of file
+        return obj.full_name
diff --git a/src/document/serializers.py b/src/document/serializers.py
index 9bf71bda58ccff44bb85a55141e121be895c2a55..7e24e70b6bd9e05d0172056753f489b3dc18d23c 100644
--- a/src/document/serializers.py
+++ b/src/document/serializers.py
@@ -12,11 +12,20 @@ class DocumentSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = models.Document
-        fields = ('uploaded_by', 'uploaded_at', 'name', 'description', 'file', 'uploaded_by_name', 'solution', )
+        fields = (
+            'uploaded_by',
+            'uploaded_at',
+            'name',
+            'description',
+            'file',
+            'uploaded_by_name',
+            'solution',
+        )
 
     def to_representation(self, instance):
         data = super().to_representation(instance)
-        if not data['file']: data['file']= ""
+        if not data['file']:
+            data['file'] = ""
         return data
 
     def get_uploaded_by_name(self, obj):
@@ -26,8 +35,11 @@ class DocumentSerializer(serializers.ModelSerializer):
         profile = CurrentUserMiddleware.get_current_user_profile()
         if value not in profile.solution.all():
             raise serializers.ValidationError('You dont have permission!')
-        count = models.Document.objects.filter(uploaded_by=profile, solution=value).count()
+        count = models.Document.objects.filter(
+            uploaded_by=profile, solution=value).count()
         if count >= _max_count:
-            raise serializers.ValidationError('You cant upload more than ' + str(_max_count) +
-                                              ' document to one solution!')
+            raise serializers.ValidationError(
+                'You cant upload more than ' +
+                str(_max_count) +
+                ' document to one solution!')
         return value
diff --git a/src/homework/serializers.py b/src/homework/serializers.py
index 06bb25fcd2e4959a45ddf96c81f49e63a6476a4a..1c7ec13725e7bf8f1472b33a4c0120293dc3071b 100755
--- a/src/homework/serializers.py
+++ b/src/homework/serializers.py
@@ -14,19 +14,28 @@ class TaskSerializer(serializers.ModelSerializer):
 
     def validate(self, data):
         if timezone.now() >= data['deadline']:
-            raise serializers.ValidationError('Please, enter appropriate deadline.')
+            raise serializers.ValidationError(
+                'Please, enter appropriate deadline.')
         return data
 
     def create(self, validated_data):
-        profiles = Profile.objects.filter(role="Student").exclude(user__email='')
+        profiles = Profile.objects.filter(
+            role="Student").exclude(
+            user__email='')
         for profile in profiles:
             email.new_homework(profile.user, validated_data.get('deadline'))
         return self.Meta.model.objects.create(**validated_data)
 
+
 class SolutionSerializer_Student(serializers.ModelSerializer):
     class Meta:
         model = models.Solution
-        read_only_fields = ('created_by', 'created_at', 'updated_at', 'ready', 'files')
+        read_only_fields = (
+            'created_by',
+            'created_at',
+            'updated_at',
+            'ready',
+            'files')
         fields = (
             'id',
             'task',
@@ -45,18 +54,22 @@ class SolutionSerializer_Student(serializers.ModelSerializer):
         return value
 
     def validate_accepted(self, value):
-        raise serializers.ValidationError("You don't have permission to modify accepted!")
+        raise serializers.ValidationError(
+            "You don't have permission to modify accepted!")
 
     def validate_corrected(self, value):
-        raise serializers.ValidationError("You don't have permission to modify corrected!")
+        raise serializers.ValidationError(
+            "You don't have permission to modify corrected!")
 
     def validate_note(self, value):
         if value != '':
-            raise serializers.ValidationError("You don't have permission to create note!")
+            raise serializers.ValidationError(
+                "You don't have permission to create note!")
         return value
 
     def update(self, instance, validated_data):
-        if instance.corrected is not True and validated_data.get('corrected', instance.corrected) is True:
+        if instance.corrected is not True and validated_data.get(
+                'corrected', instance.corrected) is True:
             email.homework_corrected(
                 instance.created_by.user,
                 instance.task.title,
@@ -66,13 +79,21 @@ class SolutionSerializer_Student(serializers.ModelSerializer):
 
     def create(self, validated_data):
         profile = CurrentUserMiddleware.get_current_user_profile()
-        models.Solution.objects.filter(created_by=profile, task=validated_data['task']).delete()
+        models.Solution.objects.filter(
+            created_by=profile,
+            task=validated_data['task']).delete()
         return super().create(validated_data)
 
+
 class SolutionSerializer_Staff(serializers.ModelSerializer):
     class Meta:
         model = models.Solution
-        read_only_fields = ('created_by', 'created_at', 'updated_at', 'ready', 'files')
+        read_only_fields = (
+            'created_by',
+            'created_at',
+            'updated_at',
+            'ready',
+            'files')
         fields = (
             'id',
             'task',
@@ -100,7 +121,8 @@ class SolutionSerializer_Staff(serializers.ModelSerializer):
         return value
 
     def update(self, instance, validated_data):
-        if instance.corrected is not True and validated_data.get('corrected', instance.corrected) is True:
+        if instance.corrected is not True and validated_data.get(
+                'corrected', instance.corrected) is True:
             email.homework_corrected(
                 instance.created_by.user,
                 instance.task.title,
@@ -110,5 +132,7 @@ class SolutionSerializer_Staff(serializers.ModelSerializer):
 
     def create(self, validated_data):
         profile = CurrentUserMiddleware.get_current_user_profile()
-        models.Solution.objects.filter(created_by=profile, task=validated_data['task']).delete()
-        return super().create(validated_data)
\ No newline at end of file
+        models.Solution.objects.filter(
+            created_by=profile,
+            task=validated_data['task']).delete()
+        return super().create(validated_data)
diff --git a/src/homework/views.py b/src/homework/views.py
index d6dfb940480998105a54257093dbb1dd4ca1ade8..fce43da9c8c315d38cbef91d700890bf8996e46a 100755
--- a/src/homework/views.py
+++ b/src/homework/views.py
@@ -8,7 +8,11 @@ from common import permissions
 class TasksViewSet(viewsets.ModelViewSet):
     serializer_class = serializers.TaskSerializer
     queryset = models.Task.objects.all()
-    permission_classes = (permissions.IsStaffOrReadOnlyForAuthenticated, permissions.IsStaffOrStudent, )
+    permission_classes = (
+        permissions.IsStaffOrReadOnlyForAuthenticated,
+        permissions.IsStaffOrStudent,
+    )
+
 
 class SolutionsViewSet(viewsets.ModelViewSet):
     serializer_class = serializers.SolutionSerializer_Student
diff --git a/src/stats/serializers.py b/src/stats/serializers.py
index c8ba37d0c87a0f38c76f6df6ce28b4457ea312cf..975a7d9af573980c82fa3f9aebd7aaa864968baa 100644
--- a/src/stats/serializers.py
+++ b/src/stats/serializers.py
@@ -22,7 +22,8 @@ class StaffEventSerializer(serializers.ModelSerializer):
         if 'absent' in data and 'visitors' in data:
             for i in data['absent']:
                 if i in data['visitors']:
-                    raise serializers.ValidationError('You cant add a student to absent and visitor in the same time.')
+                    raise serializers.ValidationError(
+                        'You cant add a student to absent and visitor in the same time.')
         return data
 
 
@@ -39,9 +40,11 @@ class NoteSerializer(serializers.ModelSerializer):
 
     def to_representation(self, instance):
         data = super().to_representation(instance)
-        if not data['event']: data['event']= ""
-        if not data['profile']: data['profile']= ""
-        
+        if not data['event']:
+            data['event'] = ""
+        if not data['profile']:
+            data['profile'] = ""
+
         return data
 
     class Meta:
@@ -54,5 +57,6 @@ class NoteSerializer(serializers.ModelSerializer):
 
     def validate(self, data):
         if data['profile'] is None and data['event'] is None:
-            raise serializers.ValidationError('You have to add profile or event')
+            raise serializers.ValidationError(
+                'You have to add profile or event')
         return data