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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 release(self):
 """ Unlocks the account. """

        self.parent.send(('release-account', self.account_hash))

        response = self.parent.recv()
        if isinstance(response, Exception):
            raise response

        if response != 'ok':
            raise ValueError('unexpected response: ' + repr(response))