Import sibling module in Python

Question

I want to import sibling module.

I searched for it and got dozens of solutions. But it all didn't work at all.

This is the example structure.

test/
  + __init__.py
  + A.py

  + test_B/
    + __init__.py
    + B.py

  + test_C/
    + __init__.py
    + C.py

I tried to import module B in module C.

# import test_B.B 
# => Error!

# import test.test_B.B 
# => Error!

# from test.test_B import B
# => Error!

# from ..test_B import B
# => Error!

# from test_B import B
# => Error!

# import sys
# sys.path.insert(0, "../test_B")
# import B
# import test_B.B
# => Error!

How can I do this?

Answer 1

I found a method.

import sys
import os

sys.path.append(os.path.dirname(os.path.dirname(__file__))
from test_B import B

This method works good.