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In a module residing inside a package, i have the need to use a function defined within the __init__.py of that package. how can i import the package within the module that resides within the package, so i can use that function?

Importing __init__ inside the module will not import the package, but instead a module named __init__, leading to two copies of things with different names...

Is there a pythonic way to do this?

CharlesB
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5 Answers5

48

Also, starting in Python 2.5, relative imports are possible. e.g.:

from . import foo

Quoting from http://docs.python.org/tutorial/modules.html#intra-package-references:

Starting with Python 2.5, in addition to the implicit relative imports described above, you can write explicit relative imports with the from module import name form of import statement. These explicit relative imports use leading dots to indicate the current and parent packages involved in the relative import. From the surrounding module for example, you might use:

from . import echo
from .. import formats
from ..filters import equalizer
Brian Clapper
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    This does not answer the question of how to import from `__init__.py`. – BrenBarn Mar 01 '14 at 21:24
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    @BrenBarn: yet this is the way to import it; when you import the *package*, the `__init__.py` file serves as the effective namespace. You should never import `__init__.py` directly. – Martijn Pieters Dec 12 '14 at 14:43
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This doesn't exactly answer your question, but I'm going to suggest that you move the function outside of the __init__.py file, and into another module inside that package. You can then easily import that function into your other module. If you want, you can have an import statement in the __init__.py file that will import that function (when the package is imported) as well.

mipadi
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5

If the package is named testmod and your init file is therefore testmod/__init__.py and your module within the package is submod.py then from within submod.py file, you should just be able to say import testmod and use whatever you want that's defined in testmod.

Eli Courtwright
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I'm not totally sure what the situation is, but this may solve your "different name" problem:

import __init__ as top
top.some_function()

Or maybe?:

from __init__ import some_function
some_function()
cdleary
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    This does work, but at least in cPython 2.7 the interpreter considers `__init__` to be a different module than `top`, and so the `__init__.py` file gets loaded twice. – dimo414 Jul 29 '12 at 18:03
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    This is an implicit relative import, and as such won't work in python 3, and is bad practice in python 2 anyway. – habnabit Sep 29 '14 at 17:34
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    This still creates `sys.modules['__init__']`. Basically, the `__init__.py` module *should never be directly imported*. Import the package (the directory name) instead. – Martijn Pieters Dec 12 '14 at 14:44
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In Django, the file manage.py has from django.core.management import execute_manager, but execute_manager is not a module. It is a function within the __init__.py module of the management directory.

Esteban Küber
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