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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_get_bucket_notification(data):
 """ Parser for a get_bucket_notification response from S3. :param data: Body of response from get_bucket_notification. :return: Returns bucket notification configuration """

    root = S3Element.fromstring('GetBucketNotificationResult', data)

    notifications = _parse_add_notifying_service_config(
        root, {},
        'TopicConfigurations', 'TopicConfiguration'
    )
    notifications = _parse_add_notifying_service_config(
        root, notifications,
        'QueueConfigurations', 'QueueConfiguration'
    )
    notifications = _parse_add_notifying_service_config(
        root, notifications,
        'CloudFunctionConfigurations', 'CloudFunctionConfiguration'
    )

    return notifications