[Python] Can not deploy dash with gunicorn

First, before we start, this question does not have a solution in this answer

I have the simplest structure. A folder called app and inside an empty __init__.py as well as this app2.py

# app/app2.py
import dash
from dash import html

# Create the Dash app
app = dash.Dash(__name__)

# Define the layout
app.layout = html.Div([
html.H1("Hello Dash!"),
html.P("This is a simple Dash application.")
])

# Expose the Flask server for Gunicorn
server = app.server

if __name__ == "__main__":
app.run(debug=True)


Very simple!. When I do python -m app.app2 I can see my dash running on http://127.0.0.1:8050/.

However when I try to run it with gunicorn (from the correct folder! - so many LLMs have told me " you are probably running it from inside app") it always fails

$ gunicorn app.app2:server --bind 0.0.0.0:8050
[2025-08-28 15:50:48 +0900] [794954] [INFO] Starting gunicorn 23.0.0
[2025-08-28 15:50:48 +0900] [794954] [INFO] Listening at: http://0.0.0.0:8050 (794954)
[2025-08-28 15:50:48 +0900] [794954] [INFO] Using worker: sync
[2025-08-28 15:50:48 +0900] [794955] [INFO] Booting worker with pid: 794955
[2025-08-28 15:50:48 +0900] [794955] [ERROR] Exception in worker process
Traceback (most recent call last):
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/arbiter.py", line 608, in spawn_worker
worker.init_process()
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/workers/base.py", line 135, in init_process
self.load_wsgi()
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/workers/base.py", line 147, in load_wsgi
self.wsgi = self.app.wsgi()
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/app/base.py", line 66, in wsgi
self.callable = self.load()
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/app/wsgiapp.py", line 57, in load
return self.load_wsgiapp()
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/app/wsgiapp.py", line 47, in load_wsgiapp
return util.import_app(self.app_uri)
File "/home/me/miniconda3/envs/py310/lib/python3.10/site-packages/gunicorn/util.py", line 370, in import_app
mod = importlib.import_module(module)
File "/home/me/miniconda3/envs/py310/lib/python3.10/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
File "<frozen importlib._bootstrap>", line 1004, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'app.app2'
[2025-08-28 15:50:48 +0900] [794955] [INFO] Worker exiting (pid: 794955)
[2025-08-28 15:50:48 +0900] [794954] [ERROR] Worker (pid:794955) exited with code 3
[2025-08-28 15:50:48 +0900] [794954] [ERROR] Shutting down: Master
[2025-08-28 15:50:48 +0900] [794954] [ERROR] Reason: Worker failed to boot.


What is the problem here? and how can I deploy the app with guvicorn?

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