as to the traceback - I am not 100% sure, but it looks like the unhandled SyntaxError exception in your program is intercepted by Apport, which is disabled by default in stable releases. During this process it try (among other things) to import module
numbers from _decimal, but it actually imports your numbers.py. as a result numbers.py is executed and you see the output as well as the AttributeError
If you can't explain it to a six year old, you don't understand it yourself, Albert Einstein
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs