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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_address(self, address, vpnid):
 """Release a specific lease, called after delete_client_entry"""

        query = address + "?action=releaseAddress&vpnId=" + vpnid
        request_url = self._build_url(['Lease', query])
        return self._do_request('DELETE', request_url)