Cross import in the same directory

Question

I'm using Python 3 with Django and I try to make cross imports which fails and I don't know why... Here is the structure:

|--my_project
   |-- system
     |--__init__.py
     |-- a.py
     |-- b.py

a.py

from .b import TestB
class TestA(object):
    pass

b.py

from .a import TestA
class TestB(object):
    pass

The import in a.py works. But the one in b.py doesn't work: ImportError: cannot import name 'TestA'. I also tried using absolute path (from myproject.system.a import TestA but with no luck). Any idea about the problem?

score 1 · Answer 1 · edited May 23 '17 at 12:30

1

There're several approaches you can use to address the cross-imports problem:

Re-organize your modules so that there're no cross-imports, i.e. put the classes to a single module, etc.
Replace from module import foo with import module and use full names.
Put imports at the end of modules (not recommended).

See also Circular imports in Python.

edited May 23 '17 at 12:30

Community

1
1

answered Dec 16 '15 at 09:03

Eugene Yarmash

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score 0 · Accepted Answer · answered Dec 16 '15 at 08:52

Putting imports at the end of your a.py and b.py should fix issues. If it doesn't help you try to move import into class definition block, so replace

from .a import TestA
Class TestB(object):
    pass

to

Class TestB(object):
    from .a import TestA
    pass

Small Suggestion: do not use relative imports.

Cross import in the same directory

2 Answers2