Is there a way to detect that the interpreter that executes the code is Jython or CPython?

I have another post: Jython does not catch Exceptions. For this case, if I know the interpreter is Jython, I can have different code that should work.

if JYTHON:sys.path.insert(0, os.path.dirname(__file__))from utils import *
else:from .utils import *

There is an official way to do it! :-) Please have a look at

http://docs.python.org/2/library/platform.html#platform.python_implementation

Returns a string identifying the Python implementation. Possible return values are: ‘CPython’, ‘IronPython’, ‘Jython’, ‘PyPy’.

New in version 2.6.

I did not know that before.

Old answer:

There probably is no standardized interface, but you can use some educated guessing, based on e.g. sys.executable (http://docs.python.org/2/library/sys.html#sys.executable), and sys.version. Furthermore, some interpreters for sure provide features that are specific to them, which you can make use of.