Detect python version in shell script

Question

I\'d like to detect if python is installed on a Linux system and if it is, which python version is installed.

How can I do it? Is there something more graceful than

Answer 1

python -c 'import sys; print sys.version_info'

or, human-readable:

python -c 'import sys; print(".".join(map(str, sys.version_info[:3])))'