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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 policy(self):
 """Returns policy which contains this ioclass."""

        policies = VNXIOPolicy.get(cli=self._cli)
        ret = None
        for policy in policies:
            contained = policy.ioclasses.name
            if self._get_name() in contained:
                ret = VNXIOPolicy.get(name=policy.name, cli=self._cli)
                break
        return ret