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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 logout_listener(app, user):
 """Connect to the user_logged_out signal. :param app: The Flask application. :param user: The :class:`invenio_accounts.models.User` instance. """

    @after_this_request
    def _commit(response=None):
        if hasattr(session, 'sid_s'):
            delete_session(session.sid_s)
        # Regenerate the session to avoid session fixation vulnerabilities.
        session.regenerate()
        current_accounts.datastore.commit()
        return response