diff --git a/proton b/proton
index 16d2b66c..7eb51faa 100755
--- a/proton
+++ b/proton
@@ -1556,7 +1556,7 @@ class Session:
             remote_debug_proc.kill()
             try:
                 remote_debug_proc.communicate(2)
-            except subprocess.TimeoutExpired as e:
+            except subprocess.TimeoutExpired:
                 log("terminate remote debugger")
                 remote_debug_proc.terminate()
                 remote_debug_proc.communicate()