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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 handle_context_missing(self):
 """ Called whenever there is no trace entity to access or mutate. """

        if self.context_missing == 'RUNTIME_ERROR':
            log.error(MISSING_SEGMENT_MSG)
            raise SegmentNotFoundException(MISSING_SEGMENT_MSG)
        else:
            log.error(MISSING_SEGMENT_MSG)