The documentation of the built-in compile() function is not 100% clear but I think it says that giving the "optimize=1" argument turns "__debug__" to false in the compiled code ( https://docs.python.org/3.5/library/functions.html?highlight=compile#compile ).  It doesn't work this way in practice, though:

    python3.5
    >>> exec(compile("print(__debug__)", "exec", "exec", optimize=1))
    True

I'd recommend to fix either the documentation or the source code.