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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 _hex_ids(self, dev_list):
 """! Build a USBID map for a device list @param disk_list List of disks in a system with USBID decoration @return Returns map USBID -> device file in /dev @details Uses regular expressions to get a USBID (TargeTIDs) a "by-id" symbolic link """

        for dl in dev_list:
            match = self.nlp.search(dl)
            if match:
                yield match.group("usbid"), _readlink(dl)