python：在包名称空间中导入模块

Question

I wonder if there is some standard way to do something like

import scipy as sp
from scipy import interpolate as sp.interpolate

that is not allowed.

Specifically:

1. I'd like to know if there is some reason why the above is not allowed. If I'm developing my own package foo, it seems reasonable to pollute its namespace as little as possible.

2. Things like

    import scipy as sp __import__('scipy.interpolate') 

   do the job, but are not all that nice and the docs recommend not to use __import__ , unless strictly necessarily. Similarly

    import importlib import scipy as sp importlib.import_module('scipy.interpolate',sp) 

does the job, but it is still ugly, even longer and puts importlib in the namespace...

Answer 1

Imported modules are treated like regular objects so if you really want to you can import a module and assign it to an arbitrary variable like so

import scipy as sp
from scipy import interpolate 
sp.interpolate = interpolate

sp.interpolate will behave as expected, it just points to the interpolate module whenever you call sp.interpolate. They are the same object underneath, ie

print sp.interpolate is interpolate
>>> True

Then to finally remove the original 'interpolate' pointer call

del interpolate