[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

voila/tornado/kernel_websocket_handler.py

@@ -18,6 +18,7 @@
 
     JUPYTER_SERVER_2 = False
 
+
 def read_header_from_binary_message(ws_msg: bytes) -> Optional[Dict]:
     """Read message header using the v1 protocol."""
 
@@ -32,11 +33,10 @@ def read_header_from_binary_message(ws_msg: bytes) -> Optional[Dict]:
     except Exception:
         return
 
+
 if JUPYTER_SERVER_2:
     SUPPORTED_SUBPROTOCOL = ["v1.kernel.websocket.jupyter.org"]
 
-
-
     class VoilaKernelWebsocketHandler(WebsocketHandler):
 
         _ALL_EXECUTION_DATA = {}