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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 _getEventFromUid(self, request, uid):
 """Try and find a child event with the given UID."""

        event = getEventFromUid(request, uid)
        if event.get_ancestors().filter(id=self.id).exists():
            # only return event if it is a descendant
            return event