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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 sendFeatureReport(self, report, report_num=0):
 """ Send a feature report. """

        length = len(report) + 1
        buf = bytearray(length)
        buf[0] = report_num
        buf[1:] = report
        self._ioctl(
            _HIDIOCSFEATURE(length),
            (ctypes.c_char * length).from_buffer(buf),
            True,
        )