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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 address(self):
 """ Should be called to get client direct address @method address @returns {String} client direct address """

        if self.isDirect():
            base36 = self._iban[4:]
            asInt = int(base36, 36)
            return to_checksum_address(pad_left_hex(baseN(asInt, 16), 20))

        return ""