Unexpected (?) result with regular expressions

[guraknugen]

Hi!

I'm running Python3 in Manjaro Linux 18.1.5 and I want to ”emulate” sed. Here's an example in Bash using sed, this is the result I want:

Output:
~ $ echo "libreoffice-still 6.2.8-4" | sed -r 's/[^0-9]*([0-9\.\-]*)/LibreOffice \1/'
LibreOffice 6.2.8-4

I thought this would work in Python, but obviously it doesn't:

import subprocess, re
print(re.sub('[^0-9]*([0-9\.\-]*)', r'LibreOffice \1', "libreoffice-still 6.2.8-4"))

Output:
LibreOffice 6.2.8-4LibreOffice

As you can see I used the exact same regular expressions, but the result is different and I don't understand why and what to do about it.
What am I doing wrong that makes ”LibreOffice” appear at the end of the result? I'm obviously missing something here…