Threaded Flask app gives OSError: [Errno 98] Address already in use in Jenkins job

I am starting my Flask app in the thread and when I test it in local environment it works perfectly but whenever I run on Jenkins it gives an already in use error.

Here is my main test application to start in jenkins pipeline

python3.8 -m pytest -n 1 --reruns 1 -v -m Smoke --tb=short --instafail --durations=0

then inside the pytest_collection_finish i use

flask_thread = threading.Thread(target=run_flask_app)flask_thread.daemon = Trueflask_thread.start()wait_for_trigger()

and here is my flask codes

from flask import Flask, requestfrom threading import Eventfrom werkzeug.serving import run_simpleimport loggingapp = Flask(__name__)test_ready_event = Event()logging.basicConfig(filename='flask_thread.log', level=logging.DEBUG,                    format='%(asctime)s - %(levelname)s - %(message)s')@app.route('/trigger', methods=['GET'])def trigger_test_continue():    test_ready_event.set()    print("Trigger received. Signalling pytest to continue.")    logging.info("Trigger received. Signalling pytest to continue.")    return "Continuing tests.", 200def run_flask_app():    logging.info("Starting Flask app.")    run_simple('0.0.0.0', 5055, app, use_reloader=False, use_debugger=True)def stop_flask_app():    func = request.environ.get('werkzeug.server.shutdown')    if func is None:        raise RuntimeError('Not running with the Werkzeug Server')    func()    logging.info("Flask app stopped.")def wait_for_trigger():    print("Waiting for the trigger to continue tests...")    logging.info("Waiting for the trigger to continue tests...")    test_ready_event.wait()    print("Trigger received. Continuing with tests.")    logging.info("Trigger received. Continuing with tests.")

Error

Exception in thread Thread-1:Traceback (most recent call last):  File "/usr/lib/python3.8/threading.py", line 932, in _bootstrap_inner    self.run()  File "/usr/lib/python3.8/threading.py", line 870, in run    self._target(*self._args, **self._kwargs)  File "/var/lib/path/execution_stopper.py", line 22, in run_flask_app    run_simple('0.0.0.0', 5055, app, use_reloader=False, use_debugger=True)  File "/usr/local/lib/python3.8/dist-packages/werkzeug/serving.py", line 1052, in run_simple    inner()  File "/usr/local/lib/python3.8/dist-packages/werkzeug/serving.py", line 996, in inner    srv = make_server(  File "/usr/local/lib/python3.8/dist-packages/werkzeug/serving.py", line 862, in make_server    return BaseWSGIServer(  File "/usr/local/lib/python3.8/dist-packages/werkzeug/serving.py", line 740, in __init__    HTTPServer.__init__(self, server_address, handler)  File "/usr/lib/python3.8/socketserver.py", line 452, in __init__    self.server_bind()  File "/usr/lib/python3.8/http/server.py", line 138, in server_bind    socketserver.TCPServer.server_bind(self)  File "/usr/lib/python3.8/socketserver.py", line 466, in server_bind    self.socket.bind(self.server_address)OSError: [Errno 98] Address already in use

when i run this in jenkins machine

sudo netstat -tulpn | grep :5005

gives

tcp        0      0 0.0.0.0:5005            0.0.0.0:*               LISTEN      1636790/python3.8