diff --git a/apps/logs/signals.py b/apps/logs/signals.py
index 2520698..e493301 100644
--- a/apps/logs/signals.py
+++ b/apps/logs/signals.py
@@ -1,10 +1,10 @@
 import getpass
 
-from tfjm.middlewares import get_current_authenticated_user, get_current_ip
 from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
 from rest_framework.renderers import JSONRenderer
 from rest_framework.serializers import ModelSerializer
+from tfjm.middlewares import get_current_authenticated_user, get_current_ip
 
 from .models import Changelog
 
diff --git a/apps/participation/apps.py b/apps/participation/apps.py
index bb84d56..2ec3fd0 100644
--- a/apps/participation/apps.py
+++ b/apps/participation/apps.py
@@ -2,7 +2,7 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 from django.apps import AppConfig
-from django.db.models.signals import post_save, pre_delete, pre_save
+from django.db.models.signals import post_save, pre_save
 
 
 class ParticipationConfig(AppConfig):
diff --git a/apps/participation/management/commands/fix_matrix_channels.py b/apps/participation/management/commands/fix_matrix_channels.py
index 2dece36..7fbd742 100644
--- a/apps/participation/management/commands/fix_matrix_channels.py
+++ b/apps/participation/management/commands/fix_matrix_channels.py
@@ -4,9 +4,9 @@
 import os
 
 from asgiref.sync import async_to_sync
-from tfjm.matrix import Matrix, RoomPreset, RoomVisibility
 from django.core.management import BaseCommand
 from registration.models import AdminRegistration, Registration
+from tfjm.matrix import Matrix, RoomPreset, RoomVisibility
 
 
 class Command(BaseCommand):
diff --git a/apps/participation/management/commands/fix_sympa_lists.py b/apps/participation/management/commands/fix_sympa_lists.py
index 3892e0d..bbe1af9 100644
--- a/apps/participation/management/commands/fix_sympa_lists.py
+++ b/apps/participation/management/commands/fix_sympa_lists.py
@@ -1,11 +1,11 @@
 # Copyright (C) 2020 by Animath
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-from tfjm.lists import get_sympa_client
 from django.core.management import BaseCommand
 from django.db.models import Q
 from participation.models import Team
 from registration.models import CoachRegistration, StudentRegistration
+from tfjm.lists import get_sympa_client
 
 
 class Command(BaseCommand):
diff --git a/apps/participation/models.py b/apps/participation/models.py
index f2b7123..380936d 100644
--- a/apps/participation/models.py
+++ b/apps/participation/models.py
@@ -2,21 +2,17 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 import os
-import re
 
-from registration.models import VolunteerRegistration
-from tfjm.lists import get_sympa_client
-from tfjm.matrix import Matrix, RoomPreset, RoomVisibility
-from django.core.exceptions import ObjectDoesNotExist
 from django.core.validators import RegexValidator
 from django.db import models
 from django.db.models import Index
-from django.template.loader import render_to_string
 from django.urls import reverse_lazy
 from django.utils import timezone
 from django.utils.crypto import get_random_string
-from django.utils.text import format_lazy
 from django.utils.translation import gettext_lazy as _
+from registration.models import VolunteerRegistration
+from tfjm.lists import get_sympa_client
+from tfjm.matrix import Matrix, RoomPreset, RoomVisibility
 
 
 class Team(models.Model):
@@ -197,6 +193,9 @@ class Tournament(models.Model):
             return Synthesis.objects.filter(final_solution=True)
         return Synthesis.objects.filter(participation__tournament=self)
 
+    def __str__(self):
+        return repr(self)
+
     class Meta:
         verbose_name = _("tournament")
         verbose_name_plural = _("tournaments")
@@ -271,12 +270,14 @@ class Pool(models.Model):
     def solutions(self):
         return Solution.objects.filter(participation__in=self.participations, final_solution=self.tournament.final)
 
+    def __str__(self):
+        return repr(self)
+
     class Meta:
         verbose_name = _("pool")
         verbose_name_plural = _("pools")
 
 
-
 class Solution(models.Model):
     participation = models.ForeignKey(
         Participation,
@@ -302,6 +303,9 @@ class Solution(models.Model):
         default="",
     )
 
+    def __str__(self):
+        return repr(self)
+
     class Meta:
         verbose_name = _("solution")
         verbose_name_plural = _("solutions")
@@ -337,6 +341,9 @@ class Synthesis(models.Model):
         default="",
     )
 
+    def __str__(self):
+        return repr(self)
+
     class Meta:
         verbose_name = _("synthesis")
         verbose_name_plural = _("syntheses")
diff --git a/apps/participation/signals.py b/apps/participation/signals.py
index 14f3830..1b7f68a 100644
--- a/apps/participation/signals.py
+++ b/apps/participation/signals.py
@@ -1,8 +1,8 @@
 # Copyright (C) 2020 by Animath
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-from tfjm.lists import get_sympa_client
 from participation.models import Participation, Team
+from tfjm.lists import get_sympa_client
 
 
 def create_team_participation(instance, created, **_):
@@ -33,4 +33,3 @@ def update_mailing_list(instance: Team, **_):
             for coach in instance.coachs.all():
                 get_sympa_client().subscribe(coach.user.email, f"equipe-{instance.trigram.lower()}", False,
                                              f"{coach.user.first_name} {coach.user.last_name}")
-
diff --git a/apps/participation/tables.py b/apps/participation/tables.py
index d38cd90..075b317 100644
--- a/apps/participation/tables.py
+++ b/apps/participation/tables.py
@@ -54,20 +54,3 @@ class ParticipationTable(tables.Table):
         model = Team
         fields = ('name', 'trigram', 'problem',)
         template_name = 'django_tables2/bootstrap4.html'
-
-
-class VideoTable(tables.Table):
-    participation_name = tables.LinkColumn(
-        'participation:participation_detail',
-        args=[tables.A("participation__pk")],
-        verbose_name=lambda: _("name").capitalize(),
-        accessor=tables.A("participation__team__name"),
-    )
-
-    class Meta:
-        attrs = {
-            'class': 'table table condensed table-striped',
-        }
-        model = Team
-        fields = ('participation_name', 'link',)
-        template_name = 'django_tables2/bootstrap4.html'
diff --git a/apps/participation/views.py b/apps/participation/views.py
index efd923c..9599615 100644
--- a/apps/participation/views.py
+++ b/apps/participation/views.py
@@ -4,9 +4,6 @@
 from io import BytesIO
 from zipfile import ZipFile
 
-from tfjm.lists import get_sympa_client
-from tfjm.matrix import Matrix
-from tfjm.views import AdminMixin
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.contrib.sites.models import Site
 from django.core.exceptions import PermissionDenied
@@ -22,6 +19,9 @@ from django.views.generic.edit import FormMixin, ProcessFormView
 from django_tables2 import SingleTableView
 from magic import Magic
 from registration.models import AdminRegistration
+from tfjm.lists import get_sympa_client
+from tfjm.matrix import Matrix
+from tfjm.views import AdminMixin
 
 from .forms import JoinTeamForm, ParticipationForm, RequestValidationForm, TeamForm, ValidateParticipationForm
 from .models import Participation, Team
diff --git a/apps/registration/models.py b/apps/registration/models.py
index 00ded2f..f096450 100644
--- a/apps/registration/models.py
+++ b/apps/registration/models.py
@@ -1,7 +1,6 @@
 # Copyright (C) 2020 by Animath
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-from tfjm.tokens import email_validation_token
 from django.contrib.sites.models import Site
 from django.db import models
 from django.template import loader
@@ -11,6 +10,7 @@ from django.utils.encoding import force_bytes
 from django.utils.http import urlsafe_base64_encode
 from django.utils.translation import gettext_lazy as _
 from polymorphic.models import PolymorphicModel
+from tfjm.tokens import email_validation_token
 
 
 class Registration(PolymorphicModel):
diff --git a/apps/registration/signals.py b/apps/registration/signals.py
index f8a3a82..a0b6a21 100644
--- a/apps/registration/signals.py
+++ b/apps/registration/signals.py
@@ -1,9 +1,9 @@
 # Copyright (C) 2020 by Animath
 # SPDX-License-Identifier: GPL-3.0-or-later
 
+from django.contrib.auth.models import User
 from tfjm.lists import get_sympa_client
 from tfjm.matrix import Matrix
-from django.contrib.auth.models import User
 
 from .models import AdminRegistration, Registration
 
diff --git a/apps/registration/templatetags/search_results_tables.py b/apps/registration/templatetags/search_results_tables.py
index 795bd75..318e7d0 100644
--- a/apps/registration/templatetags/search_results_tables.py
+++ b/apps/registration/templatetags/search_results_tables.py
@@ -4,7 +4,7 @@
 from django import template
 from django_tables2 import Table
 from participation.models import Participation, Team
-from participation.tables import ParticipationTable, TeamTable, VideoTable
+from participation.tables import ParticipationTable, TeamTable
 
 from ..models import Registration
 from ..tables import RegistrationTable
diff --git a/apps/registration/tests.py b/apps/registration/tests.py
index b4384e3..9317ed2 100644
--- a/apps/registration/tests.py
+++ b/apps/registration/tests.py
@@ -3,7 +3,6 @@
 
 import os
 
-from tfjm.tokens import email_validation_token
 from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
 from django.contrib.sites.models import Site
@@ -14,6 +13,7 @@ from django.urls import reverse
 from django.utils.encoding import force_bytes
 from django.utils.http import urlsafe_base64_encode
 from participation.models import Team
+from tfjm.tokens import email_validation_token
 
 from .models import AdminRegistration, CoachRegistration, StudentRegistration
 
diff --git a/apps/registration/views.py b/apps/registration/views.py
index fa5d476..6df0e26 100644
--- a/apps/registration/views.py
+++ b/apps/registration/views.py
@@ -3,8 +3,6 @@
 
 import os
 
-from tfjm.tokens import email_validation_token
-from tfjm.views import AdminMixin
 from django.conf import settings
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.contrib.auth.models import User
@@ -18,6 +16,8 @@ from django.utils.translation import gettext_lazy as _
 from django.views.generic import CreateView, DetailView, RedirectView, TemplateView, UpdateView, View
 from django_tables2 import SingleTableView
 from magic import Magic
+from tfjm.tokens import email_validation_token
+from tfjm.views import AdminMixin
 
 from .forms import CoachRegistrationForm, PhotoAuthorizationForm, SignupForm, StudentRegistrationForm, UserForm
 from .models import Registration, StudentRegistration
diff --git a/tfjm/settings.py b/tfjm/settings.py
index 6e47c82..c3f7b3b 100644
--- a/tfjm/settings.py
+++ b/tfjm/settings.py
@@ -68,7 +68,7 @@ INSTALLED_APPS = [
     'participation',
 ]
 
-if "test" not in sys.argv and not "makemigrations" in sys.argv:  # pragma: no cover
+if "test" not in sys.argv and "makemigrations" not in sys.argv:  # pragma: no cover
     INSTALLED_APPS += [
         'cas_server',
         'django_extensions',