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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 check(self):
 """Check that the resource exists. :raises ResourceNotFound: if the resource doesn't exists """

        if self.fq_name:
            self['uuid'] = self._check_fq_name(self.fq_name)
        elif self.uuid:
            self['fq_name'] = self._check_uuid(self.uuid)
        return True