diff --git a/check_systemd_timer.py b/check_systemd_timer.py
index 6d12903..07d897c 100755
--- a/check_systemd_timer.py
+++ b/check_systemd_timer.py
@@ -1,9 +1,12 @@
 #!/usr/bin/env python3
-
 import argparse
+import re
+import subprocess
 import sys
 import traceback
+from datetime import datetime
 
+import humanfriendly
 from dateutil import tz
 
 from checker import nagios
@@ -13,17 +16,11 @@ from checker.result import quit_check
 sys.path.insert(0, "/usr/lib/python3/dist-packages")
 import dbus
 
-import re
-import subprocess
-from datetime import datetime
-
-import humanfriendly
-
 SYSTEMCTL_TIMERS_RE = re.compile(
     r'^(([A-Za-z]*\s[0-9]{4}-[0-9]{2}-[0-9]{2}\s*[0-9]{2}:[0-9]{2}:[0-9]{2}\s[A-Z]*)|n\/a)\s*((([0-9]*[a-z]*\s)*left)|n\/a)\s*(([A-Za-z]*\s[0-9]{4}-[0-9]{2}-[0-9]{2}\s[0-9]{2}:[0-9]{2}:[0-9]{2}\s[A-Z]*)|n\/a)\s*(([0-9A-Za-z\s]*\sago)|n\/a)\s*([A-Za-z\-_]*.timer)\s*(([A-Za-z\-_]*.service)|\s*)')
 
 
-def get_next_elapse(timer_name):
+def get_next_elapse(timer_name) -> tuple[None, Exception] | tuple[dict, None]:
     try:
         output = subprocess.check_output(["systemctl", "list-timers", "--all"], universal_newlines=True)
         lines = output.split('\n')