如何从python中的另一个文件夹导入？

Question

I've seen tips on how to import from a subfolder . The problem is importing from another folder in the same parent folder. The current structure is like this:

test 
__init__.py
|-- folder1
|-- __init__.py
| |-- A.py
|-- folder2
| |-- __init__.py
| |-- B.py

A.py is:

hi = 1 
print "hi", hi

B.py is:

from folder1 import A

print "imported"

When I do python B.py , I get an error:

  File "B.py", line 1, in <module>
    from folder1 import A
ImportError: No module named folder1

How can I import A.py? Ideally, folder structure does not change.

Answer 1

The problem here is that folder1 and folder2 are subpackages, and the package is the parent directory ie test .

Whatever path the parent directory of test is will need to be in your sys.path . You can do this, for example, with the PYTHONPATH environment variable.

Then you should have, in module B.py :

from test.folder1 import A