diff --git a/npm-scripts.mjs b/npm-scripts.mjs
index c6634b1..b6131b7 100644
--- a/npm-scripts.mjs
+++ b/npm-scripts.mjs
@@ -243,7 +243,7 @@ function installPythonDevDeps()
 
 	const PYP3 = process.env.PIP3 || 'pip3';
 
-	executeCmd(`${PYP3} install flake8`);
+	executeCmd(`${PYP3} install flake8 mypy`);
 }
 
 function checkRelease()
diff --git a/worker/handler.py b/worker/handler.py
index 93dedd3..db4e7f8 100644
--- a/worker/handler.py
+++ b/worker/handler.py
@@ -3,7 +3,6 @@
 import asyncio
 from aiortc import (
     RTCConfiguration,
-    RTCDataChannel,
     RTCPeerConnection,
     RTCRtpTransceiver,
     RTCSessionDescription,