Execute the actions necessary to perform a `molecule login` and
        returns None.

        :return: None

def execute(self):
        """
        Execute the actions necessary to perform a `molecule login` and
        returns None.

        :return: None
        """
        c = self._config
        if ((not c.state.created) and c.driver.managed):
            msg = 'Instances not created.  Please create instances first.'
            util.sysexit_with_message(msg)

        hosts = [d['name'] for d in self._config.platforms.instances]
        hostname = self._get_hostname(hosts)
        self._get_login(hostname)