58

I'm totally new to Python and I know this question was asked many times, but unfortunately it seems that my situation is a bit different... I have created a package (or so I think). The catalog tree is like this:

mydir
    lib   (__init__.py)
        mod1  (__init__.py, mod11.py)

In parenthesis there are files in the catalog. Both __init__.py files are zero length.

The file mydir/lib/mod1/mod11.py contains the following:

def mod12():
    print "mod12"

Now, I run python, then import lib, which works OK, then lib.mod11() or lib.mod12().

Either of the last two gives me the subject error message. Actually dir(lib) after Step 2 does not display mod11 or mod12 either. It seems I'm missing something really simple.

(I'm using Python 2.6 in Ubuntu 10.10)

Thank you

1
  • 2
    The error message in the subject is incomplete. It may be helpful to post the full error message here in the body. Commented Feb 2, 2011 at 7:08

4 Answers 4

49

When you import lib, you're importing the package. The only file to get evaluated and run in this case is the 0 byte __init__.py in the lib directory.

If you want access to your function, you can do something like this from lib.mod1 import mod1 and then run the mod12 function like so mod1.mod12().

If you want to be able to access mod1 when you import lib, you need to put an import mod1 inside the __init__.py file inside the lib directory.

Sign up to request clarification or add additional context in comments.

1 Comment

I tried to add import mod1 in lib/__init__.py. When I import lib, I got an error ModuleNotFoundError: No module named 'mod1'.
32

More accurately, your mod1 and lib directories are not modules, they are packages. The file mod11.py is a module.

Python does not automatically import subpackages or modules. You have to explicitly do it, or "cheat" by adding import statements in the initializers.

>>> import lib
>>> dir(lib)
['__builtins__', '__doc__', '__file__', '__name__', '__package__', '__path__']
>>> import lib.pkg1
>>> import lib.pkg1.mod11
>>> lib.pkg1.mod11.mod12()
mod12

An alternative is to use the from syntax to "pull" a module from a package into you scripts namespace.

>>> from lib.pkg1 import mod11

Then reference the function as simply mod11.mod12().

Comments

6

The way I would do it is to leave the __ init__.py files empty, and do:

import lib.mod1.mod11
lib.mod1.mod11.mod12()

or

from lib.mod1.mod11 import mod12
mod12()

You may find that the mod1 dir is unnecessary, just have mod12.py in lib.

Comments

4

My solution is put those imports in __init__.py of lib:

in file: __init__.py
import mod1

Then,

import lib
lib.mod1

would work fine.

Comments

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.