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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 ensure_parent_id(self):
 """If current trace_parent has no span_id, generate one, then return it This is used to generate a span ID which the RUM agent will use to correlate the RUM transaction with the backend transaction. """

        if self.trace_parent.span_id == self.id:
            self.trace_parent.span_id = "%016x" % random.getrandbits(64)
            logger.debug("Set parent id to generated %s", self.trace_parent.span_id)
        return self.trace_parent.span_id