Q:

Dockerfile run python command not working

I have a dockerfile like this:
FROM python:3
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
ADD reports /code/
RUN pip install -r requirements.txt
ADD . /code/
RUN ls -l /code/reports/report/manage.py  # gives expected result
RUN ls -l /code/reports/build_static/  # gives expected result
RUN python /code/reports/report/manage.py build full_report.views.RenderView  # does not work

Everything works fine except for the last command which runs a python package (django-bakery) through manage.py build. I don't get any errors.
This command should output some files inside build_static directory in the container.
If I ssh into the container and run the command manually then it is working. I inserted the full path with /code/ to make sure that they match and created all necessary directories beforehand.
This is how I build the container: 
docker-compose run django /bin/bash

This is my docker-compose:
version: '3'

services:
  django:
    build: .
    volumes:
      - .:/code
    ports:
      - "8000:8000"

I wonder how come it is working when I run the command manually through bash inside the container, but not working with the command in the dockerfile.
Thanks!
Update (it seems that the files are created, but then if I check on them they aren't there):
Step 12/12 : RUN ls -l /code/reports/build_static/
 ---> Running in e294563d26d5
total 11080
-rw-r--r-- 1 root root 11339956 Apr 30 10:53 index.html
drwxr-xr-x 7 root root     4096 Apr 30 10:53 static
Removing intermediate container e294563d26d5
 ---> b8e72da8ee5c
Successfully built b8e72da8ee5c
Successfully tagged image_django:latest
WARNING: Image for service django was built because it did not already exist. To rebuild this image you must use `docker-compose build` or `docker-compose up --build`.
root@7483853ecc45:/code# ls -l reports/build_static/
total 0

A:

Try following steps and let me know output:
FROM python:3
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
ADD reports /code/
RUN pip install -r requirements.txt
ADD . /code/
RUN ls -l /code/reports/report/manage.py  # gives expected result
RUN ls -l /code/reports/build_static/  # gives expected result
RUN python /code/reports/report/manage.py build full_report.views.RenderView  
RUN ls -l /code/reports/build_static/  # should give you expected list of files

Give me output for the last step.
I'll help you out based on output.

