unable to load app 0 (mountpoint='') (callable not found or import error) - Docker Flask app with uWSGI

Consider the following file structure:

/app/detecter_script
|- Dockerfile
|- detecter.py
|- ...

detecter.py

import flask
from werkzeug.middleware.dispatcher import DispatcherMiddleware
from prometheus_client import make_wsgi_app

app = flask.Flask(__name__)
app.config['JSON_SORT_KEYS'] = False
app.wsgi_app = DispatcherMiddleware(app.wsgi_app, {
    '/metrics': make_wsgi_app()
})

@app.route('/pred', method=['post'])
def pred_info():
    xxx

Dockerfile

...
WORKDIR /app/detecter_script
...
CMD uwsgi --http 0.0.0.0:8123 -w detecter:app --master --enable-threads

My problem is that when I run docker run image_name:version, I get the following error: unable to load app 0 (mountpoint='') (callable not found or import error) and no app loaded. going in full dynamic mode. I tried many