My docker file is as follows:

#Use python 3.6 image
FROM python:3.6
ENV PYTHONUNBUFFERED 1

#install required packages
RUN apt-get update
RUN apt-get install libsasl2-dev libldap2-dev libssl-dev python3-dev psmisc -y

#install a pip package
#Note: This pip package has a completely configured django project in it
RUN pip install <pip-package>

#Run a script
#Note: Here appmanage.py is a file inside the pip installed location(site-packages), but it will be accessible directly without cd to the folder
RUN appmanage.py appconfig appadd.json

#The <pip-packge> installed comes with a built in django package, so running it with following CMD
#Note: Here manage.py is present inside the pip package folder but it is accesible directly
CMD ["manage.py","runserver","0.0.0.0:8000"]

When i run :

sudo docker build -t test-app .

The steps in dockerfile till: RUN appmanage.py appconfig runs sucessfully as expected but after that i get the error:

The command '/bin/sh -c appmanage.py appconfig ' returned a non-zero code: 137

When i google for the error i get suggestions like memory is not sufficient. But i have verified, the system(centos) is having enough memory.

Additional info

The commandline output during the execution of RUN appmanage.py appconfig is :

Step 7/8 : RUN appmanage.py appconfig
 ---> Running in 23cffaacc81f

======================================================================================
configuring katana apps...
 Please do not quit (or) kill the server manually, wait until the server closes itself...!
======================================================================================
Performing system checks...

System check identified no issues (0 silenced).
February 08, 2020 - 12:01:45
Django version 2.1.2, using settings 'katana.wui.settings'
Starting development server at http://127.0.0.1:9999/
Quit the server with CONTROL-C.
9999/tcp:
    20Killed

As described, the command RUN appmanage.py appconfig appAdd.json run successfully as expected and reported that System check identified no issues (0 silenced)..

Moreover, the command "insisted" on killing itself and return exit code of 137. The minimum changes for this to work is to update your Dockerfile to be like

...
#Run a script
#Note: Here appmanage.py is a file inside the pip installed location(site-packages), but it will be accessible directly without cd to the folder
RUN appmanage.py appconfig appAdd.json || true
...

This will just forcefully ignore the return exit code from the previous command and carry on the build.