Circular dependency in Python

python circular-dependency
Ram Rachum picture Ram Rachum · May 21, 2009 · Viewed 76.2k times · Source

I have two files, node.py and path.py, which define two classes, Node and Path, respectively.

Up to today, the definition for Path referenced the Node object, and therefore I had done

from node.py import *

in the path.py file.

However, as of today I created a new method for Node that references the Path object.

I had problems when trying to import path.py: I tried it, and when the program ran and called the Path method that uses Node, an exception rose about Node not being defined.

What do I do?

Answer

Nadia Alramli picture Nadia Alramli · May 21, 2009

Importing Python Modules is a great article that explains circular imports in Python.

The easiest way to fix this is to move the path import to the end of the node module.

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