Question

Is there a way to tidy-up the following code, rather than a series of nested try/except statements?

try:     import simplejson as json except ImportError:     try:         import json     except ImportError:         try:             from django.utils import simplejson as json         except:             raise 'Requires either simplejson, Python 2.6 or django.utils!' 

Answer 1

I found the following function at http://mail.python.org/pipermail/python-list/2007-May/441896.html. It seems to work quite well, and I’m pretty sure the way its importing won’t stomp on any existing imports you might already have.

def module_exists(module_name):     try:         mod = __import__(module_name)     except ImportError:         return False     else:         return True  if module_exists('simplejson'):     import simplejson as json elif module_exists('json'):     import json elif module_exists('django.utils'):     from django.utils import simplejson as json else:     raise ImportError('Requires either simplejson, Python 2.6 or django.utils') 

I know this seems like more code, but the function is reusable elsewhere if you’re doing a lot of this.