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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 absolute(self):
 """ The FQDN as a string in absolute form """

        if not self.is_valid:
            raise ValueError('invalid FQDN `{0}`'.format(self.fqdn))

        if self.is_valid_absolute:
            return self.fqdn

        return '{0}.'.format(self.fqdn)