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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 sense_dep(self, target):
 """Search for a DEP Target in active communication mode. Because the PN531 does not implement the extended frame syntax for host controller communication, it can not support the maximum payload size of 254 byte. The driver handles this by modifying the length-reduction values in atr_req and atr_res. """

        if target.atr_req[15] & 0x30 == 0x30:
            self.log.warning("must reduce the max payload size in atr_req")
            target.atr_req[15] = (target.atr_req[15] & 0xCF) | 0x20

        target = super(Device, self).sense_dep(target)
        if target is None:
            return

        if target.atr_res[16] & 0x30 == 0x30:
            self.log.warning("must reduce the max payload size in atr_res")
            target.atr_res[16] = (target.atr_res[16] & 0xCF) | 0x20

        return target