lint: fix

doc/index.rst

@@ -315,7 +315,7 @@ To setup your development environment, you need to do something like this:
     git clone https://github.com/deltachat/mailadm
     python3 -m venv venv
     . venv/bin/activate
-    pip install pytest tox pytest-xdist pytest-timeout pyzbar
+    pip install pytest tox pytest-xdist pytest-timeout pyzbar black ruff
     sudo apt install -y libzbar0
     pip install .
 

src/mailadm/app.py

@@ -1,6 +1,7 @@
 """
 help gunicorn and other WSGI servers to instantiate a web instance of mailadm
 """
+
 import threading
 
 from mailadm.bot import get_admbot_db_path

src/mailadm/conn.py

@@ -275,7 +275,7 @@ def get_expired_users(self, sysdate):
                 expired_users.append(user)
                 continue
             mc_user = self.get_mailcow_connection().get_user(user.addr)
-            if not mc_user:
+            if mc_user is None:
                 logging.warning("user %s doesn't exist in mailcow", user.addr)
                 continue
             last_login = mc_user.last_login