python 3.x - ValueError: attempted relative import beyond top-level package -

i playing the python's import system in order understand better how works, , encountered problem. have following structure

pkg/     __init__.py     c.py     d.py      subpkg/         __init__.py         a.py         b.py

inside a.py have following code:

from . import b .. import d

and inside c.py have following:

import subpkg.a

now receive following error:

valueerror: attempted relative import beyond top-level package

but why? how can solve it? running c.py idle, , pkg should considered package, since has __init__.py file.

the first import works fine, it's following doesn't work:

from .. import d

because attempting import parent package, apparently cannot, weird reason.

python 3 changed import system every time want module around 1 working, need relative imports (unless mess python_path or sys.path).

the correct usage here should be

from .subpkg import

when working idle, have totally different environment. therefore, add current location path imports work again.

try:

sys.path.insert(0, '')

it might weird, greater good

ps: if last thing not work -- don't have idle environment right -- because work directory set wrong.

Scrio