Buster image contains Python 3.7 (and not 3.8)

[Nicholas-Autio-Mitchell]

Are the images containing the newly released Python version 3.8 up and running? I understood so from the README and listed tags.

I would like to create a custom image based on the python3.8-buster image.

I created a simple Dockerfile with the contents:

FROM python:buster
RUN pip install numpy

and build the image with:

$  docker build -t my_buster_image .

I create and enter a container from the built image and check which python versions are available:

$  docker run -it my_buster_image /bin/bash

root@9f04520130a0:/# which -a python
/usr/local/bin/python
/usr/local/bin/python
/usr/bin/python

root@9f04520130a0:/# which -a python3.8
# empty return

root@9f04520130a0:/# which -a python3.7
/usr/local/bin/python3.7
/usr/local/bin/python3.7
/usr/bin/python3.7

---

Questions:

1. Have I done something incorrectly?
2. How can I get an image running 3.8 and install my own packages?

---

Remarks:

1. I also tried using the developers Python image that holds many python versions. That does contain Python 3.8, however is built in such a way that I cannot simply build from it and add a line:

RUN pip install numpy

[Nicholas-Autio-Mitchell]

I took the (generated) Dockerfile from the Python repository (under: python/3.8/buster/Dockerfile) and was able to append my simple pip install ... line, and successfully build the image. It took a total of 25 minutes - partly because numpy had to also be compiled as pip didn't have a wheel available.

Then running the same as above in the container, I get:

$  docker run -it my_buster_image /bin/bash

root@c93e1f8d7221:/# which -a python
/usr/local/bin/python
/usr/local/bin/python
/usr/bin/python

root@c93e1f8d7221:/# which -a python3.8
/usr/local/bin/python3.8
/usr/local/bin/python3.8

root@c93e1f8d7221:/# which -a python3.7
/usr/bin/python3.7

So Python version 3.8 is there (and 3.7, which is perhaps unexpected).

I could also use my own numpy as expected:

root@c93e1f8d7221:/# python3.8
Python 3.8.0 (default, Oct 16 2019, 00:17:43) 
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.

>>> import numpy as np
>>> np.random.random(10)
array([0.6470034 , 0.26120951, 0.54700188, 0.25709831, 0.70114084,
       0.85906728, 0.85868124, 0.67499514, 0.34384473, 0.45151778])

[wglambert]

Maybe the updated image wasn't pushed yet to Dockerhub when you had tried using it docker-library/official-images#6788
It would have been 3 hours after the merge

It's updated now so I'm going to close

$ docker pull python:buster
buster: Pulling from library/python
4a56a430b2ba: Already exists 
4b5cacb629f5: Already exists 
14408c8d4f9a: Already exists 
ea67eaa7dd42: Already exists 
4d134ac3fe4b: Already exists 
4c55f6f5d7f0: Pull complete 
254e105a5240: Pull complete 
24b2d397f4c8: Pull complete 
b0394dbabd13: Pull complete 
Digest: sha256:110dd1117dabc28bbf7bcc8f6d24ace3e999880af7772a18f0ea6a29458dcb8b                                                                               
Status: Downloaded newer image for python:buster

$ docker run -it --rm python:buster bash
root@e795dace5711:/# python -V
Python 3.8.0 

root@e795dace5711:/# pip --version
pip 19.3 from /usr/local/lib/python3.8/site-packages/pip (python 3.8)

root@e795dace5711:/# which -a python3.8
/usr/local/bin/python3.8                                                                                                                                      
/usr/local/bin/python3.8