module has no attribute

Question

I have a directory with a number of .py files in it. each file defines some classes. I also have an empty __init__.py in the directory.

For example:

myproject
    __init__.py
    mymodule
        __init__.py
        api.py
        models.py
        views.py

I am trying to import mymodule and access the classes defined in all these files:

from myproject import mymodule

print mymodule.api.MyClass

It gives me an error saying that mymodule has no attribute api. Why? And why I can access just one of the files (models.py) and not the others?

In [2]: dir(banners)
Out[2]:
['__builtins__',
 '__doc__',
 '__file__',
 '__name__',
 '__package__',
 '__path__',
 'models']

score 88 · Accepted Answer · answered Jan 17 '12 at 17:56

88

The problem is submodules are not automatically imported. You have to explicitly import the api module:

import myproject.mymodule.api
print myproject.mymodule.api.MyClass

If you really insist on api being available when importing myproject.mymodule you can put this in myproject/mymodule/__init__.py:

import myproject.mymodule.api

Then this will work as expected:

from myproject import mymodule

print mymodule.api.MyClass

answered Jan 17 '12 at 17:56

Rob Wouters

1

hi, i tried this but i still get a ModuleNotFoundError: No module named lib.myfunction. any thoughts? the funny thing is if i just import lib, there is no error. if i call lib.myfunction after that it also throws an error. – yl_low Apr 10 '18 at 11:26
Isn't this a bit cumbersome? Is there a way to switch on importing of sub-modules (with the full qualifying names, e.g foo.bar.baz) by default? – Amir Rosenfeld May 01 '19 at 15:20
I'm fine doing the full import, but in the rest of the code I'd like to drop `myproject` and refer to `mymodule.api` which does not seem to be possible? – Alper Aug 16 '19 at 10:03

score 21 · Answer 2 · answered Mar 29 '20 at 11:03

21

If you are an idiot, like me, then also check whether you didn't name your python file the same as the module you are trying to import.

answered Mar 29 '20 at 11:03

Olaf

4

Yes, this is a strange piece of Python rubric, that the filename must be different from the module name. Be warned! – CharlesW Dec 13 '20 at 13:18
Oh wow, that's a difficult one to google! – PatrickT Oct 17 '21 at 11:13

score 0 · Answer 3 · answered Jan 17 '12 at 17:45

0

Modules don't work like that.

from myproject.mymodule import api
print api.MyClass

answered Jan 17 '12 at 17:45

Daniel Roseman

I know I can do that. Is it possible to do using the dotted names? – akonsu Jan 17 '12 at 17:47
2

@akonsu, simply do `import myproject.mymodule.api` then and access it through `myproject.mymodule.api.MyClass`. – Rob Wouters Jan 17 '12 at 17:50
well, i think this is a question about the language in general, not about how I can get my code to work. I am curious as to whether this can be achieved. can I make it access my classes through 'mymodule.api...' without the leading 'myproject'? – akonsu Jan 17 '12 at 17:53
you could do `import myproject.mymodule as mymodule` but it seems confusing to me – Matt Jan 17 '12 at 18:00

score -1 · Answer 4 · answered Jan 17 '12 at 17:49

-1

You need an __init__.py in the myproject directory too. So your module structure should be:

myproject
    __init__.py
    mymodule
        __init__.py
        api.py
        models.py
        views.py

answered Jan 17 '12 at 17:49

Akash

6

That's exactly the module structure in the question... – SenhorLucas Sep 11 '20 at 19:19

4 Answers4