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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 serialize_me(self, arn, event_time, tech, item=None):
 """Dumps the proper JSON for the schema. If the event is too big, then don't include the item. :param arn: :param event_time: :param tech: :param item: :return: """

        payload = {
            'arn': arn,
            'event_time': event_time,
            'tech': tech
        }

        if item:
            payload['item'] = item

        else:
            payload['event_too_big'] = True

        return self.dumps(payload).data.replace('<empty>', '')