diff --git a/.gitignore b/.gitignore
index 71572ed17..7f0c6c5d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,6 +20,7 @@ Thumbs.db
 # Virtual Environment
 .virtualenv*/*
 .venv/*
+server/.venv
 
 ## Compatibility
 # OS4-Submodules
diff --git a/.travis.yml b/.travis.yml
index dc89cfd38..a71818155 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -109,7 +109,7 @@ jobs:
       script:
         - flake8 openslides tests
         - isort --check-only --diff --recursive openslides tests
-        - black --check --diff --target-version py36 openslides tests
+        - black --check --diff openslides tests
         - mypy openslides/ tests/
         - pytest --cov --cov-fail-under=75
 
@@ -122,7 +122,7 @@ jobs:
       script:
         - flake8 openslides tests
         - isort --check-only --diff --recursive openslides tests
-        - black --check --diff --target-version py36 openslides tests
+        - black --check --diff openslides tests
         - mypy openslides/ tests/
         - pytest --cov --cov-fail-under=75
 
diff --git a/server/openslides/agenda/models.py b/server/openslides/agenda/models.py
index cbb608330..b3fddb52d 100644
--- a/server/openslides/agenda/models.py
+++ b/server/openslides/agenda/models.py
@@ -360,8 +360,6 @@ class ListOfSpeakersManager(BaseManager):
 
 
 class ListOfSpeakers(RESTModelMixin, models.Model):
-    """
-    """
 
     access_permissions = ListOfSpeakersAccessPermissions()
     objects = ListOfSpeakersManager()
diff --git a/server/openslides/assignments/migrations/0010_voting_3.py b/server/openslides/assignments/migrations/0010_voting_3.py
index b3f8bf115..54b8f7d72 100644
--- a/server/openslides/assignments/migrations/0010_voting_3.py
+++ b/server/openslides/assignments/migrations/0010_voting_3.py
@@ -20,5 +20,5 @@ class Migration(migrations.Migration):
         migrations.RemoveField(model_name="assignmentpoll", name="votesabstain"),
         migrations.RemoveField(model_name="assignmentpoll", name="votesno"),
         migrations.RemoveField(model_name="assignmentpoll", name="published"),
-        migrations.RemoveField(model_name="assignmentrelateduser", name="elected",),
+        migrations.RemoveField(model_name="assignmentrelateduser", name="elected"),
     ]
diff --git a/server/openslides/assignments/migrations/0012_assignment_vote_unique_together.py b/server/openslides/assignments/migrations/0012_assignment_vote_unique_together.py
index 2a7e822ea..bc3722295 100644
--- a/server/openslides/assignments/migrations/0012_assignment_vote_unique_together.py
+++ b/server/openslides/assignments/migrations/0012_assignment_vote_unique_together.py
@@ -13,6 +13,6 @@ class Migration(migrations.Migration):
 
     operations = [
         migrations.AlterUniqueTogether(
-            name="assignmentvote", unique_together={("user", "option")},
+            name="assignmentvote", unique_together={("user", "option")}
         ),
     ]
diff --git a/server/openslides/assignments/views.py b/server/openslides/assignments/views.py
index c86fa4c5a..8fbdd6274 100644
--- a/server/openslides/assignments/views.py
+++ b/server/openslides/assignments/views.py
@@ -465,14 +465,14 @@ class AssignmentPollViewSet(BasePollViewSet):
                         )
                     if (
                         poll.pollmethod == AssignmentPoll.POLLMETHOD_YNA
-                        and value not in ("Y", "N", "A",)
+                        and value not in ("Y", "N", "A")
                     ):
                         raise ValidationError(
                             {"detail": "Every value must be Y, N or A"}
                         )
                     elif (
                         poll.pollmethod == AssignmentPoll.POLLMETHOD_YN
-                        and value not in ("Y", "N",)
+                        and value not in ("Y", "N")
                     ):
                         raise ValidationError({"detail": "Every value must be Y or N"})
 
@@ -526,7 +526,7 @@ class AssignmentPollViewSet(BasePollViewSet):
         for option_id, result in data.items():
             option = options.get(pk=option_id)
             vote = AssignmentVote.objects.create(
-                option=option, user=vote_user, value=result, weight=weight,
+                option=option, user=vote_user, value=result, weight=weight
             )
             inform_changed_data(vote, no_delete_on_restriction=True)
             inform_changed_data(option, no_delete_on_restriction=True)
diff --git a/server/openslides/core/migrations/0028_projector_size_3.py b/server/openslides/core/migrations/0028_projector_size_3.py
index 81b623232..13a612b37 100644
--- a/server/openslides/core/migrations/0028_projector_size_3.py
+++ b/server/openslides/core/migrations/0028_projector_size_3.py
@@ -9,6 +9,4 @@ class Migration(migrations.Migration):
         ("core", "0027_projector_size_2"),
     ]
 
-    operations = [
-        migrations.RemoveField(model_name="projector", name="height",),
-    ]
+    operations = [migrations.RemoveField(model_name="projector", name="height")]
diff --git a/server/openslides/core/migrations/0030_voting_projection_defaults.py b/server/openslides/core/migrations/0030_voting_projection_defaults.py
index 0dd201757..a264404b2 100644
--- a/server/openslides/core/migrations/0030_voting_projection_defaults.py
+++ b/server/openslides/core/migrations/0030_voting_projection_defaults.py
@@ -14,7 +14,7 @@ def add_poll_projection_defaults(apps, schema_editor):
 
     projectiondefaults.append(
         ProjectionDefault(
-            name="assignment_poll", display_name="Ballots", projector=default_projector,
+            name="assignment_poll", display_name="Ballots", projector=default_projector
         )
     )
     projectiondefaults.append(
diff --git a/server/openslides/motions/access_permissions.py b/server/openslides/motions/access_permissions.py
index 6000b552d..dcfde0d6c 100644
--- a/server/openslides/motions/access_permissions.py
+++ b/server/openslides/motions/access_permissions.py
@@ -53,11 +53,15 @@ class MotionAccessPermissions(BaseAccessPermissions):
                     # Parse values of restriction field.
                     # If at least one restriction is ok, permissions are granted.
                     for value in restriction:
-                        if value in (
-                            "motions.can_see_internal",
-                            "motions.can_manage_metadata",
-                            "motions.can_manage",
-                        ) and await async_has_perm(user_id, value):
+                        if (
+                            value
+                            in (
+                                "motions.can_see_internal",
+                                "motions.can_manage_metadata",
+                                "motions.can_manage",
+                            )
+                            and await async_has_perm(user_id, value)
+                        ):
                             permission = True
                             break
                         elif value == "is_submitter" and is_submitter:
diff --git a/server/openslides/motions/migrations/0035_motion_vote_unique_together.py b/server/openslides/motions/migrations/0035_motion_vote_unique_together.py
index 0678fba94..25d49d5af 100644
--- a/server/openslides/motions/migrations/0035_motion_vote_unique_together.py
+++ b/server/openslides/motions/migrations/0035_motion_vote_unique_together.py
@@ -13,6 +13,6 @@ class Migration(migrations.Migration):
 
     operations = [
         migrations.AlterUniqueTogether(
-            name="motionvote", unique_together={("user", "option")},
-        ),
+            name="motionvote", unique_together={("user", "option")}
+        )
     ]
diff --git a/server/openslides/motions/models.py b/server/openslides/motions/models.py
index 66a3ec8ea..73cee0870 100644
--- a/server/openslides/motions/models.py
+++ b/server/openslides/motions/models.py
@@ -193,7 +193,7 @@ class Motion(RESTModelMixin, AgendaItemWithListOfSpeakersMixin, models.Model):
     """
 
     motion_block = models.ForeignKey(
-        "MotionBlock", on_delete=SET_NULL_AND_AUTOUPDATE, null=True, blank=True,
+        "MotionBlock", on_delete=SET_NULL_AND_AUTOUPDATE, null=True, blank=True
     )
     """
     ForeignKey to one block of motions.
diff --git a/server/openslides/motions/views.py b/server/openslides/motions/views.py
index 55f1f7afa..a9d7253dc 100644
--- a/server/openslides/motions/views.py
+++ b/server/openslides/motions/views.py
@@ -1744,8 +1744,6 @@ class StateViewSet(ModelViewSet, ProtectedErrorMessageMixin):
         return result
 
     def create(self, request, *args, **kwargs):
-        """
-        """
         result = super().create(request, *args, **kwargs)
         workflow_id = request.data[
             "workflow_id"
diff --git a/server/openslides/utils/cache.py b/server/openslides/utils/cache.py
index bfa87b2b7..31828a7b7 100644
--- a/server/openslides/utils/cache.py
+++ b/server/openslides/utils/cache.py
@@ -165,7 +165,7 @@ class ElementCache:
         logger.info("Done saving the cache data.")
 
     def _build_cache_get_elementid_model_mapping(
-        self, config_only: bool = False,
+        self, config_only: bool = False
     ) -> Dict[str, str]:
         """
         Do NOT call this in an asynchronous context!
diff --git a/server/openslides/utils/consumer_autoupdate_strategy.py b/server/openslides/utils/consumer_autoupdate_strategy.py
index 0c4922028..63bde7021 100644
--- a/server/openslides/utils/consumer_autoupdate_strategy.py
+++ b/server/openslides/utils/consumer_autoupdate_strategy.py
@@ -98,5 +98,5 @@ class ConsumerAutoupdateStrategy:
             self.client_change_id = max_change_id
             # It will be send, so we can set the client_change_id
             await self.consumer.send_json(
-                type="autoupdate", content=autoupdate, in_response=in_response,
+                type="autoupdate", content=autoupdate, in_response=in_response
             )
diff --git a/server/openslides/utils/websocket.py b/server/openslides/utils/websocket.py
index 42e5b802f..4157d7ce2 100644
--- a/server/openslides/utils/websocket.py
+++ b/server/openslides/utils/websocket.py
@@ -143,7 +143,7 @@ class ProtocollAsyncJsonWebsocketConsumer(AsyncCompressedJsonWebsocketConsumer):
         )
 
     async def send_exception(
-        self, e: BaseWebsocketException, silence_errors: Optional[bool] = True,
+        self, e: BaseWebsocketException, silence_errors: Optional[bool] = True
     ) -> None:
         """
         Send generic error messages with a custom status code (see above) and a text message.
diff --git a/server/openslides/utils/websocket_client_messages.py b/server/openslides/utils/websocket_client_messages.py
index d66eb1f58..ce8c62759 100644
--- a/server/openslides/utils/websocket_client_messages.py
+++ b/server/openslides/utils/websocket_client_messages.py
@@ -62,7 +62,7 @@ class Notify(BaseWebsocketClientMessage):
         perm = self.notify_permissions.get(content["name"])
         if perm is not None and not await async_has_perm(consumer.user_id, perm):
             raise NotAuthorizedException(
-                f"You need '{perm}' to send this message.", in_response=id,
+                f"You need '{perm}' to send this message.", in_response=id
             )
         else:
             # Some logging
diff --git a/server/tests/integration/assignments/test_polls.py b/server/tests/integration/assignments/test_polls.py
index aa1a07257..e0bc8ee34 100644
--- a/server/tests/integration/assignments/test_polls.py
+++ b/server/tests/integration/assignments/test_polls.py
@@ -105,7 +105,7 @@ def create_assignment_polls():
 class CreateAssignmentPoll(TestCase):
     def advancedSetUp(self):
         self.assignment = Assignment.objects.create(
-            title="test_assignment_ohneivoh9caiB8Yiungo", open_posts=1,
+            title="test_assignment_ohneivoh9caiB8Yiungo", open_posts=1
         )
         self.assignment.add_candidate(self.admin)
 
@@ -576,7 +576,7 @@ class UpdateAssignmentPoll(TestCase):
 
     def test_patch_groups_to_empty(self):
         response = self.client.patch(
-            reverse("assignmentpoll-detail", args=[self.poll.pk]), {"groups_id": []},
+            reverse("assignmentpoll-detail", args=[self.poll.pk]), {"groups_id": []}
         )
         self.assertHttpStatusVerbose(response, status.HTTP_200_OK)
         poll = AssignmentPoll.objects.get()
@@ -869,7 +869,7 @@ class VoteAssignmentPollAnalogYNA(VoteAssignmentPollBaseTestClass):
     def test_wrong_data_format(self):
         self.start_poll()
         response = self.client.post(
-            reverse("assignmentpoll-vote", args=[self.poll.pk]), [1, 2, 5],
+            reverse("assignmentpoll-vote", args=[self.poll.pk]), [1, 2, 5]
         )
         self.assertHttpStatusVerbose(response, status.HTTP_400_BAD_REQUEST)
         self.assertFalse(AssignmentVote.objects.exists())
@@ -1063,7 +1063,7 @@ class VoteAssignmentPollNamedYNA(VoteAssignmentPollBaseTestClass):
         option2 = self.poll2.options.get()
         # Do request to poll with option2 (which is wrong...)
         response = self.client.post(
-            reverse("assignmentpoll-vote", args=[self.poll.pk]), {str(option2.id): "Y"},
+            reverse("assignmentpoll-vote", args=[self.poll.pk]), {str(option2.id): "Y"}
         )
         self.assertHttpStatusVerbose(response, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(AssignmentVote.objects.count(), 0)
diff --git a/server/tests/integration/motions/test_polls.py b/server/tests/integration/motions/test_polls.py
index 8714a103c..2b93759bd 100644
--- a/server/tests/integration/motions/test_polls.py
+++ b/server/tests/integration/motions/test_polls.py
@@ -488,7 +488,7 @@ class UpdateMotionPoll(TestCase):
 
     def test_patch_groups_to_empty(self):
         response = self.client.patch(
-            reverse("motionpoll-detail", args=[self.poll.pk]), {"groups_id": []},
+            reverse("motionpoll-detail", args=[self.poll.pk]), {"groups_id": []}
         )
         self.assertHttpStatusVerbose(response, status.HTTP_200_OK)
         poll = MotionPoll.objects.get()
@@ -641,7 +641,7 @@ class VoteMotionPollAnalog(TestCase):
     def test_vote_missing_data(self):
         self.start_poll()
         response = self.client.post(
-            reverse("motionpoll-vote", args=[self.poll.pk]), {"Y": "4", "N": "22.6"},
+            reverse("motionpoll-vote", args=[self.poll.pk]), {"Y": "4", "N": "22.6"}
         )
         self.assertHttpStatusVerbose(response, status.HTTP_400_BAD_REQUEST)
         self.assertFalse(MotionPoll.objects.get().get_votes().exists())
@@ -879,7 +879,7 @@ class VoteMotionPollNamed(TestCase):
 
 
 class VoteMotionPollNamedAutoupdates(TestCase):
-    """ 3 important users:
+    """3 important users:
     self.admin: manager, has can_see, can_manage, can_manage_polls (in admin group)
     self.user1: votes, has can_see perms and in in delegate group
     self.other_user: Just has can_see perms and is NOT in the delegate group.
@@ -1018,7 +1018,7 @@ class VoteMotionPollNamedAutoupdates(TestCase):
 
 
 class VoteMotionPollPseudoanonymousAutoupdates(TestCase):
-    """ 3 important users:
+    """3 important users:
     self.admin: manager, has can_see, can_manage, can_manage_polls (in admin group)
     self.user: votes, has can_see perms and in in delegate group
     self.other_user: Just has can_see perms and is NOT in the delegate group.
diff --git a/server/tests/integration/users/test_viewset.py b/server/tests/integration/users/test_viewset.py
index 8af4588fa..9f7dad1e7 100644
--- a/server/tests/integration/users/test_viewset.py
+++ b/server/tests/integration/users/test_viewset.py
@@ -723,7 +723,7 @@ class GroupCreate(TestCase):
         self.client.login(username="admin", password="admin")
 
         response = self.client.post(
-            reverse("group-list"), {"name": "Test name ldr59xq2mvt96rdayhju"},
+            reverse("group-list"), {"name": "Test name ldr59xq2mvt96rdayhju"}
         )
 
         self.assertEqual(response.status_code, status.HTTP_201_CREATED)