Python module import - why are components only available when explicitly imported?

Question

I have recently installed scikit-image version 0.11.3. I am using python 2.7.10. When I import the entire module I cannot access the io module.

import skimag         


        

Answer 1

It's simply the way Python handles modules.

One reason is that it would make importing one module very slow if cpython needed to scan for submodules, import all of them and then import all of their submodules.

The other reason is "better be explicit than implicit". Why should Python import everything possible when you only need a small fraction of a package with a complex module hierarchy.

Instead of from skimage import io you can also write

import skimage.io

then skimage.io.imread will be found.