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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_message_event(proto_message, span, message_event_type, message_id=1):
 """Adds a MessageEvent to the span based off of the given protobuf message """

    span.add_time_event(
        time_event=time_event.TimeEvent(
            datetime.utcnow(),
            message_event=time_event.MessageEvent(
                message_id,
                type=message_event_type,
                uncompressed_size_bytes=proto_message.ByteSize()
            )
        )
    )