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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 usable_id(cls, id):
 """ Retrieve id from single input. """

        hcs = cls.from_fqdn(id)
        if hcs:
            return [hc_['id'] for hc_ in hcs]

        try:
            return int(id)
        except (TypeError, ValueError):
            pass