Detecting whether a module is imported inside the App Engine environment

Question

What I want to do is patch an existing Python module that uses urllib2 to run on App Engine, but I don't want to break it so it can be used elsewhere. So I'm looking for a quick solution to test if the module is imported in the App Engine environment or not. Catching ImportError on urllib2 might not be the best solution.

Answer 1

You could simply use sys.modules to test if a module has been imported (I'm using unicodedata as an example):

>>> import sys
>>> 'unicodedata' in sys.modules
False
>>> import unicodedata
>>> 'unicodedata' in sys.modules
True