ImportError: Couldn't import Django in running Docker image - django

Question

I am so new in Docker and I have dockerized a simple django application and this is Dockerfile :
FROM python:3.8-slim-buster
ENV PYTHONUNBUFFERED 1
WORKDIR /app
COPY . .
RUN pip freeze > requirements.txt
RUN pip3 install -r requirements.txt
CMD ["python3","manage.py", "runserver","0.0.0.0:8000
and this docker-compose.yml:
version: "3.9"
services:
db:
image: postgres
volumes:
- ./data/db:/var/lib/postgresql/data
environment:
- POSTGRES_DB=postgres
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=postgres
web:
build: .
command: python manage.py runserver 0.0.0.0:8000
volumes:
- .:/code
ports:
- "8000:8000"
depends_on:
- d
and this is the packages in requirements.txt :
asgiref==3.4.1
Django==3.2.9
pytz==2021.3
sqlparse==0.4.2
i have created image myapp 4 successfuly and when i tried to run this image with dcoker run myapp4 i got the following error :
Traceback (most recent call last):
File "manage.py", line 11, in main
from django.core.management import execute_from_command_line
ModuleNotFoundError: No module named 'django'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "manage.py", line 22, in <module>
main()
File "manage.py", line 13, in main
raise ImportError(
ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Did you forget to activate a virtual environment?
what am i missing here?