Traceback (most recent call last):
  File "./manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/core/management/__init__.py", line 338, in execute_from_command_line
    utility.execute()
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/core/management/__init__.py", line 312, in execute
    django.setup()
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/__init__.py", line 18, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/apps/registry.py", line 115, in populate
    app_config.ready()
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/contrib/admin/apps.py", line 22, in ready
    self.module.autodiscover()
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/contrib/admin/__init__.py", line 24, in autodiscover
    autodiscover_modules('admin', register_to=site)
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/utils/module_loading.py", line 74, in autodiscover_modules
    import_module('%s.%s' % (app_config.name, module_to_search))
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/Users/vedran/Development/edX/otto/ecommerce/ecommerce/extensions/voucher/admin.py", line 1, in <module>
    from oscar.apps.voucher.admin import *  # noqa
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/oscar/apps/voucher/admin.py", line 4, in <module>
    Voucher = get_model('voucher', 'Voucher')
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/oscar/core/loading.py", line 235, in get_model
    return apps.get_model(app_label, model_name)
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/apps/registry.py", line 202, in get_model
    return self.get_app_config(app_label).get_model(model_name.lower())
  File "/Users/vedran/Development/edX/otto/lib/python2.7/site-packages/django/apps/config.py", line 162, in get_model
    "App '%s' doesn't have a '%s' model." % (self.label, model_name))
LookupError: App 'voucher' doesn't have a 'voucher' model.