diff --git a/pkgs/additional/sane-scripts/src/lib/ssdp/sane_ssdp.py b/pkgs/additional/sane-scripts/src/lib/ssdp/sane_ssdp.py
index 0a31e7c9d..5523fc400 100644
--- a/pkgs/additional/sane-scripts/src/lib/ssdp/sane_ssdp.py
+++ b/pkgs/additional/sane-scripts/src/lib/ssdp/sane_ssdp.py
@@ -32,7 +32,7 @@ class SsdpResponse:
         return self.headers.get("LOCATION")
 
 
-def get_root_devices():
+def get_root_devices() -> list[str]:
     listener = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
     listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
     listener.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_TTL, 2)
@@ -62,7 +62,7 @@ def get_root_devices():
                     logger.info(f"root desc: {root_desc}")
                     yield root_desc
 
-def get_ips_from_location(location: str):
+def get_ips_from_location(location: str) -> tuple[str | None, str | None]:
     """
     location = URI from the Location header, e.g. http://10.78.79.1:2189/rootDesc.xml
     returns (lan, wan)
@@ -91,14 +91,14 @@ def get_ips_from_location(location: str):
             logger.info(f"got LAN = {lan} from {location}")
     return lan, wan
 
-def get_any_wan():
+def get_any_wan() -> tuple[str, str, str] | None:
     """ return (location, LAN IP, WAN IP) for the first device seen which has a WAN IP """
     for location in get_root_devices():
         lan, wan = get_ips_from_location(location)
         if lan and wan:
             return location, lan, wan
 
-def forward_port(root_device: str, proto: str, port: int, lan_ip: str, reason: str = "", duration: int = 86400):
+def forward_port(root_device: str, proto: str, port: int, lan_ip: str, reason: str = "", duration: int = 86400) -> None:
     args = [
         "upnpc",
         "-u", root_device,