ValueError: attempted relative import beyond top-l

问题:

I was playing the the Python's import system in order to understand better how it works, and I encountered another problem. I have the following structure

pkg/
    __init__.py
    c.py
    d.py

    subpkg/
        __init__.py
        a.py
        b.py

Inside a.py I have the following code:

from . import b
from .. import d

And inside c.py I have the following:

import subpkg.a

Now I receive the following error:

ValueError: attempted relative import beyond top-level package

But why? How can I solve it? I am running c.py from the IDLE, and pkg should be considered a package, since it has the __init__.py file.

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

from .. import d

Because I am attempting to import something from a parent package, but apparently I cannot, for some weird reason.

回答1:

Python 3 changed the import system so every time you want a module that is around the one you are working, you need relative imports (unless you mess with PYTHON_PATH or sys.path).

The correct usage here should be

from .subpkg import a

When you are working with IDLE, you have a totally different environment. Therefore, you could add the current location to your path so imports work again.

try:

sys.path.insert(0, '')

It might be weird, but it is for a greater good

PS: If this last thing do not work -- I don't have an IDLE environment right now -- it is probably because the work directory is set wrong.

Try this answer instead: https://stackoverflow.com/a/17361545/754991