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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 _add_to_checksum(self, checksum, value):
 """Add a byte to the checksum."""

        checksum = self._byte_rot_left(checksum, 1)
        checksum = checksum + value
        if (checksum > 255):
            checksum = checksum - 255
        self._debug(PROP_LOGLEVEL_TRACE, "C: " + str(checksum) + " V: " + str(value))
        return checksum