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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 debug_tag(self, tag):
 """Setter for the debug tag. By default, the tag is the serial of the device, but sometimes it may be more descriptive to use a different tag of the user's choice. Changing debug tag changes part of the prefix of debug info emitted by this object, like log lines and the message of DeviceError. Example: By default, the device's serial number is used: 'INFO [AndroidDevice|abcdefg12345] One pending call ringing.' The tag can be customized with `ad.debug_tag = 'Caller'`: 'INFO [AndroidDevice|Caller] One pending call ringing.' """

        self.log.info('Logging debug tag set to "%s"', tag)
        self._debug_tag = tag
        self.log.extra['tag'] = tag