[Python] twisted.internet.error.ReactorNotRestartable Error in AWS Lambda when using Kite...

I am trying to run a AWS Lambda function which acheives the following :

1. Run the code every 10 minutes, which will subscribe to tick data for one or more stocks
2. Call the function if the tick_datetime.second is between 1 and 20
3. Close the websocket and exit the code after 20 seconds or as defined by variable ttl

Below is the code :

from kiteconnect import KiteTicker
kws = KiteTicker(api_key, access_token)
tick_data = []
unique_tk = []
start_time = datetime.now(timezone("Asia/Kolkata"))

instrument_token = i_token_list
print("Tick Stock Instrument Token: ", instrument_token)

def on_ticks(ws, ticks):
tk = {}
tk['t_stamp'] = ticks[0].get("last_trade_time")
tk['last_price'] = ticks[0].get("last_price")
# print("Ticks: ",tk['t_stamp'],tk['last_price'])
return None

def on_connect(ws, response):
ws.subscribe(instrument_token)
ws.set_mode(ws.MODE_FULL, instrument_token)

def on_close(ws, code, reason):
ws.stop()

# Assign the callbacks.
kws.on_ticks = on_ticks
kws.on_connect = on_connect
kws.on_close = on_close

kws.connect(threaded=True)
# kws.connect()

while True:
def on_ticks(ws, ticks):
feed_data(ticks)

def feed_data(ticks):
for tick in ticks:
# print(tick)

tk = {}
tk['instrument_token'] = tick['instrument_token']
tk['t_stamp'] = tick["last_trade_time"].astimezone(timezone('Asia/Kolkata')).strftime("%Y-%m-%d %H:%M:%S")
tk['last_price'] = tick["last_price"]

if 0 < tick["last_trade_time"].second < 20:
tick_data.append(tk)

kws.on_ticks=on_ticks

def update_item(l_tick) :
print(json.dumps(l_ticks, indent = 2))

if (datetime.now(timezone("Asia/Kolkata")) -start_time).total_seconds() % 2 == 0:
update_dynamo_item(tick_data)
ttl_seconds = 20
if (datetime.now(timezone("Asia/Kolkata")) -start_time).total_seconds() > ttl_seconds:
update_dynamo_item(tick_data)
print(str(ttl_seconds) + " seconds passed, closing connection...")
kws.unsubscribe(instrument_token)
kws.close()
kws.stop()
print("Tick Data: ", json.dumps(tick_data, indent=2))
break


In AWS Lambda, the code is running for the first invocation of Lambda function. From the second invocation onwards, the below error is thrown :

>2025-06-26T09:19:50.536+05:30
Exception in thread Thread-2 (run):
>2025-06-26T09:19:51.356+05:30
Traceback (most recent call last):
>2025-06-26T09:19:51.416+05:30
File "/var/lang/lib/python3.13/threading.py", line 1041, in _bootstrap_inner
>2025-06-26T09:19:51.416+05:30
self.run()
>2025-06-26T09:19:51.416+05:30
~~~~~~~~^^
>2025-06-26T09:19:51.456+05:30
File "/var/lang/lib/python3.13/threading.py", line 992, in run
>2025-06-26T09:19:51.456+05:30
self._target(*self._args, **self._kwargs)
>2025-06-26T09:19:51.456+05:30
~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>2025-06-26T09:19:51.476+05:30
File "/opt/python/twisted/internet/base.py", line 695, in run
>2025-06-26T09:19:51.476+05:30
self.startRunning(installSignalHandlers=installSignalHandlers)
>2025-06-26T09:19:51.476+05:30
~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>2025-06-26T09:19:51.516+05:30
File "/opt/python/twisted/internet/base.py", line 926, in startRunning
>2025-06-26T09:19:51.516+05:30
raise error.ReactorNotRestartable()
>2025-06-26T09:19:51.536+05:30
twisted.internet.error.ReactorNotRestartable

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