Dynamic import in Python

Question

How can I make this import:

from module import *

with imp module?

Disclaimer:

• I need use imp module because I need make several statements and I want to do it dynamicly
• I need use * because I need that in the file I made the import, the variables and methods defined in module be available directly, i mean without module.method or module.variable. And I want import all variables and methods in the module because I don't know what methods or variables can be in the module in the future

• Bartek: So once you import everything from this mystery module, that you don't know what it contains, what do you plan to do with it? ;-)
• diegueus9: I'm trying to split django settings.py into several files
• Bartek: Can I recommend this? justcramer.com/2011/01/13/settings-in-django
• diegueus9: Of course you can, but I'm triyng something a little bit different

Answer 1

Here!

def load_everything_from(module_names):
 g = globals()
 for module_name in module_names:
 m = __import__(module_name)
 names = getattr(m, '__all__', None)
 if names is None:
 names = [name for name in dir(m) if not name.startswith('_')]
 for name in names:
 g[name] = getattr(m, name)

I am kind of making things up there a little bit with trying to find an __all__ symbol first and then, if that files, doing a dir() and grabbing symbols that look non-private — you would have to look at the implementation of import * to know if that resembles Python's actual logic closely enough for your purposes.

• Tadeck: Interesting, but aren't you devil's advocate by doing from module_name import * for several module names at once, skipping all the elements with names starting with "_"? Also dir()'s main purpose is interactive prompt and they are mentioning in the documentation that its behaviour may vary across releases. But indeed interesting ;)

Answer 2

If you are using django (as mentionned in comments), something like this should work

from django.utils import importlib
my_module = importlib.import_module('app.my_module')
from my_module import *

But I agree that it may be dangerous

• tm_lv: the from syntax will not work with your local my_module. You will get "my_module is not defined" instead. the import_module is analogous to "from foo import bar" so wildcard imports unfortunately won't work

Answer 3

You can do it by:

from imp import *

but remember:

Explicit is better than implicit.

(from The Zen of Python - read it by using the following command: import this)

• diegueus9: But I need use the imp module because I need made that import several times
• Tadeck: @diegueus9: I totally do not follow what you are talking about. You can do import imp in various locations (every import imp statement will be ignored after you first import imp module), you can even re-import module using reload(imp). " because I need made that import several times " is not the reason for importing everything, it is not even relevant, I believe.
• diegueus9: Sorry, I think is my bad english, but in the disclaimer I try to explain why just from imp import * doesn't work for me
• Tadeck: @diegueus9: Is it about loading modules on the basis of strings you have? Eg. you want something like import_my_module(name_of_the_module) instead of ability to call import imp anywhere you like in the code?
• diegueus9: Yes, It is. Besides I need emulate from module import * and I have a list of modules with strings