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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def autodiscover():
 """ Auto-discover INSTALLED_APPS backbone_api.py modules. """

    # This code is based off django.contrib.admin.__init__
    from django.conf import settings
    try:
        # Django versions >= 1.9
        from django.utils.module_loading import import_module
    except ImportError:
        # Django versions < 1.9
        from django.utils.importlib import import_module
    from django.utils.module_loading import module_has_submodule
    from backbone.views import BackboneAPIView  # This is to prevent a circular import issue

    for app in settings.INSTALLED_APPS:
        mod = import_module(app)
        # Attempt to import the app's backbone module.
        try:
            import_module('%s.backbone_api' % app)
        except:
            # Decide whether to bubble up this error. If the app just
            # doesn't have an backbone module, we can ignore the error
            # attempting to import it, otherwise we want it to bubble up.
            if module_has_submodule(mod, 'backbone_api'):
                raise