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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 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)