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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 _is_active_model(cls, model):
 """ Check is model app name is in list of INSTALLED_APPS """

        # We need to use such tricky way to check because of inconsistent apps names:
        # some apps are included in format "<module_name>.<app_name>" like "waldur_core.openstack"
        # other apps are included in format "<app_name>" like "nodecondcutor_sugarcrm"
        return ('.'.join(model.__module__.split('.')[:2]) in settings.INSTALLED_APPS or
                '.'.join(model.__module__.split('.')[:1]) in settings.INSTALLED_APPS)