Q:

how do i setup only python 2.7 in docker container?

I have node app and in one use case I am calling python script from node using python-shell . I am trying to setup this app on docker and my Dockerfile looks something like this
FROM debian:latest
# replace shell with bash so we can source files
RUN rm /bin/sh && ln -s /bin/bash /bin/sh
# update the repository sources list
# and install dependencies
RUN apt-get update \
&& apt-get install -y curl \
&& apt-get -y autoclean
# nvm environment variables
ENV NVM_DIR /usr/local/nvm
ENV NODE_VERSION 10.15.3
# install nvm
# https://github.com/creationix/nvm#install-script
RUN curl --silent -o- https://raw.githubusercontent.com/creationix/nvm/v0.31.2/install.sh | bash
# install node and npm
RUN source $NVM_DIR/nvm.sh \
&& nvm install $NODE_VERSION \
&& nvm alias default $NODE_VERSION \
&& nvm use default
# add node and npm to path so the commands are available
ENV NODE_PATH $NVM_DIR/v$NODE_VERSION/lib/node_modules
ENV PATH $NVM_DIR/versions/node/v$NODE_VERSION/bin:$PATH
# confirm installation
RUN node -v
RUN npm -v
RUN apt-get -y install python2.7
COPY package.json .
RUN npm install
COPY . .
CMD ["npm","run","start"]

after building and running this container when I try to invoke use case where python script gets called from node I am getting this error.
null
events.js:174
      throw er; // Unhandled 'error' event
      ^

Error: spawn /usr/lib/python2.7 EACCES
    at Process.ChildProcess._handle.onexit (internal/child_process.js:240:19)
    at onErrorNT (internal/child_process.js:415:16)
    at process._tickCallback (internal/process/next_tick.js:63:19)
Emitted 'error' event at:
    at Process.ChildProcess._handle.onexit (internal/child_process.js:246:12)
    at onErrorNT (internal/child_process.js:415:16)
    at process._tickCallback (internal/process/next_tick.js:63:19)
npm ERR! code ELIFECYCLE
npm ERR! errno 1

A:

You can use python base image
FROM PYTHON:2.7

This base image with have python pre-configured and you don't need to install python seperately. Hope it helps.
Here is the list of available image
For quick reference please check 
https://blog.realkinetic.com/building-minimal-docker-containers-for-python-applications-37d0272c52f3

