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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 realtime_comment_classifier(sender, instance, created, **kwargs):
 """ Classifies a comment after it has been created. This behaviour is configurable by the REALTIME_CLASSIFICATION MODERATOR, default behaviour is to classify(True). """

    # Only classify if newly created.
    if created:
        moderator_settings = getattr(settings, 'MODERATOR', None)
        if moderator_settings:
            if 'REALTIME_CLASSIFICATION' in moderator_settings:
                if not moderator_settings['REALTIME_CLASSIFICATION']:
                    return

        # Only classify if not a reply comment.
        if not getattr(instance, 'is_reply_comment', False):
            from moderator.utils import classify_comment
            classify_comment(instance)