Relative imports in Python 3

Question

I want to import a function from another file in the same directory.

Sometimes it works for me with from .mymodule import myfunction but sometimes I get

Answer 1

I was getting this ImportError: attempted relative import with no known parent package

In my program I was using the file from current path for importing its function.

from .filename import function

Then I modified the current path (Dot) with package name. Which resolved my issue.

from package_name.filename import function

I hope the above answer helps you.

Answer 2

If none of the above worked for you, you can specify the module explicitly.

Directory:

├── Project
│     ├── Dir
│     │    ├── __init__.py
│     │    ├── module.py
│     │    └── standalone.py

Solution:

#in standalone.py
from Project.Dir.module import ...

module - the module to be imported

Answer 3

TLDR; Append Script path to the System Path by adding following in the entry point of your python script.

import os.path
import sys
PACKAGE_PARENT = '..'
SCRIPT_DIR = os.path.dirname(os.path.realpath(os.path.join(os.getcwd(), os.path.expanduser(__file__))))
sys.path.append(os.path.normpath(os.path.join(SCRIPT_DIR, PACKAGE_PARENT)))

Thats it now you can run your project in PyCharma as well as from Terminal!!

Answer 4

Moving the file from which you are importing to an outside directory helps.
This is extra useful when your main file makes any other files in its own directory.
Ex:
Before:
Project
|---dir1
|-------main.py
|-------module1.py
After:
Project
|---module1.py
|---dir1
|-------main.py

Answer 5

Put this inside your package's __init__.py file:

# For relative imports to work in Python 3.6
import os, sys; sys.path.append(os.path.dirname(os.path.realpath(__file__)))

Assuming your package is like this:

├── project
│   ├── package
│   │   ├── __init__.py
│   │   ├── module1.py
│   │   └── module2.py
│   └── setup.py

Now use regular imports in you package, like:

# in module2.py
from module1 import class1

This works in both python 2 and 3.

Answer 6

For PyCharm users:

I also was getting ImportError: attempted relative import with no known parent package because I was adding the . notation to silence a PyCharm parsing error. PyCharm innaccurately reports not being able to find:

lib.thing import function

If you change it to:

.lib.thing import function

it silences the error but then you get the aforementioned ImportError: attempted relative import with no known parent package. Just ignore PyCharm's parser. It's wrong and the code runs fine despite what it says.