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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 get_logged_in_by(self, login, parent_zc, duration=0):
 """Use another client to get logged in via preauth mechanism by an already logged in admin. It required the domain of the admin user to have preAuthKey The preauth key cannot be created by API, do it with zmprov : zmprov gdpak <domain> """

        domain_name = zobjects.Account(name=login).get_domain()
        preauth_key = parent_zc.get_domain(domain_name)['zimbraPreAuthKey']

        rc = self.REST_PREAUTH(
            self._server_host, parent_zc._server_port, preauth_key=preauth_key)

        authToken = rc.get_preauth_token(login)

        self.login_with_authToken(authToken)