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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 parse_event_xml(self, event_data) -> dict: """Parse metadata xml."""

        event = {}

        event_xml = event_data.decode()

        message = MESSAGE.search(event_xml)
        if not message:
            return {}
        event[EVENT_OPERATION] = message.group(EVENT_OPERATION)

        topic = TOPIC.search(event_xml)
        if topic:
            event[EVENT_TOPIC] = topic.group(EVENT_TOPIC)

        source = SOURCE.search(event_xml)
        if source:
            event[EVENT_SOURCE] = source.group(EVENT_SOURCE)
            event[EVENT_SOURCE_IDX] = source.group(EVENT_SOURCE_IDX)

        data = DATA.search(event_xml)
        if data:
            event[EVENT_TYPE] = data.group(EVENT_TYPE)
            event[EVENT_VALUE] = data.group(EVENT_VALUE)

        _LOGGER.debug(event)

        return event