Import functions directly from Python 3 modules

Question

I have the following folder structure for a Python 3 project where vehicle.py is the main script and the folder stats is treated as a package containing several modules:

The cars module defines the following functions:

def neon():
    print('Neon')
    print('mpg = 32')


def mustang():
    print('Mustang')
    print('mpg = 27')

Using Python 3, I can access the functions in each module from within vehicle.py as follows:

import stats.cars as c

c.mustang()

However, I would like to access the functions defined in each module directly, but I receive an error when doing this:

import stats as st

st.mustang()
# AttributeError: 'module' object has no attribute 'mustang'

I also tried placing an __init__.py file in the stats folder with the following code:

from cars import *
from trucks import *

but I still receive an error:

import stats as st

st.mustang()
# ImportError: No module named 'cars'

I'm trying to use the same approach as NumPy such as:

import numpy as np

np.arange(10)
# prints array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])

How can I create a package like NumPy in Python 3 to access functions directly in modules?

Solution

Put an __init__.py file in the stats folder (as others have said), and put this in it:

from .cars import neon, mustang
from .trucks import truck_a, truck_b

Not so neat, but easier would be to use the * wildcard:

from .cars import *
from .trucks import *

This way, the __init__.py script does some importing for you, into its own namespace.

Now you can use functions/classes from the neon/mustang module directly after you import stats:

import stats as st
st.mustang()

Comments

[Stefan Yohansson]

import stats.cars as c === from stats import cars as c

[wigging]

I tried the __init__.py approach and still get the error.

[wigging]

I tried the __init__.py approach but I still get an error about the import not being seen. Please see my updated question.

[chepner]

You need to specify a relative import: from .cars import *.

[user2357112]

Yeah, this is Python 2-style implicit relative importing. You need the explicit .cars relative import.

[wigging]

ok, I needed the .cars import instead of just cars, the from stats.cars import * also works