#Python 2.7.9/Python 2.7.10, 127 bytes
We've had one post that used minor versions, but none that have gone to the next level down...
import types
n=len(dir(types))
print"This program wasn't written in Python 2.7.%d, it was made for Python 2.7.%d!"%(n%33,-n%52)
Try it on Ideone (Python 2.7.10) and repl.it (technically Python 2.7.2, but should give the same result as 2.7.9).
Python 2.7.10, according to the changelog:
Added an
__all__
to thetypes
module.
This pushed len(dir(types))
from 42 to 43, giving a numerical difference we can exploit to generate the desired output.