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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_config(self, retrieve='all'):
 """Implementation of get_config for IOS. Returns the startup or/and running configuration as dictionary. The keys of the dictionary represent the type of configuration (startup or running). The candidate is always empty string, since IOS does not support candidate configuration. """


        configs = {
            'startup': '',
            'running': '',
            'candidate': '',
        }

        if retrieve in ('startup', 'all'):
            command = 'show startup-config'
            output = self._send_command(command)
            configs['startup'] = output

        if retrieve in ('running', 'all'):
            command = 'show running-config'
            output = self._send_command(command)
            configs['running'] = output

        return configs