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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 __publish(topic, message, subject=None):
 """ Publish a message to a SNS topic :type topic: str :param topic: SNS topic to publish the message to :type message: str :param message: Message to send via SNS :type subject: str :param subject: Subject to use for e-mail notifications :returns: None """

    try:
        SNS_CONNECTION.publish(topic=topic, message=message, subject=subject)
        logger.info('Sent SNS notification to {0}'.format(topic))
    except BotoServerError as error:
        logger.error('Problem sending SNS notification: {0}'.format(
            error.message))

    return