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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 _enable_session_activity(self, app):
 """Enable session activity."""

        user_logged_in.connect(login_listener, app)
        user_logged_out.connect(logout_listener, app)
        from .views.settings import blueprint
        from .views.security import security, revoke_session
        blueprint.route('/security/', methods=['GET'])(security)
        blueprint.route('/sessions/revoke/', methods=['POST'])(revoke_session)