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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def process_complaint(message, notification):
 """Function to process a complaint notification"""

    mail = message['mail']
    complaint = message['complaint']

    if 'arrivalDate' in complaint:
        arrival_date = clean_time(complaint['arrivalDate'])
    else:
        arrival_date = None

    complaints = []
    for recipient in complaint['complainedRecipients']:
        # Create each Complaint. Save in a list for reference later.
        complaints += [Complaint.objects.create(
            sns_topic=notification['TopicArn'],
            sns_messageid=notification['MessageId'],
            mail_timestamp=clean_time(mail['timestamp']),
            mail_id=mail['messageId'],
            mail_from=mail['source'],
            address=recipient['emailAddress'],
            feedback_id=complaint['feedbackId'],
            feedback_timestamp=clean_time(complaint['timestamp']),
            useragent=complaint.get('userAgent'),
            feedback_type=complaint.get('complaintFeedbackType'),
            arrival_date=arrival_date
        )]

    # Send signals for each complaint.
    for complaint in complaints:
        signals.feedback.send(
            sender=Complaint,
            instance=complaint,
            message=message,
            notification=notification
        )

    logger.info('Logged %s Complaint(s)', str(len(complaints)))

    return HttpResponse('Complaint Processed')