def _find_extensions(app_label, model_name):
    ext = []

    suffix = "extensions.%s.%s" % (
        app_label, model_name.lower())
    modules = filter(None, [
        try_import((app_name, suffix) % "%s.%s")
        for app_name in settings.INSTALLED_APPS])
    modules = [mod for mod in [
        try_import("%s.%s" % (app_name, suffix))
        for app_name in settings.INSTALLED_APPS] if mod]

    for module in modules:
        for cls in get_classes(module, models.Model):
            ext.append(cls)

    return ext
dataset/ETHPy150Open rapidsms/rapidsms/rapidsms/models.py/_find_extensions/swapped operands of `%`