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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 _clean_message(message):
    '''Internal helper to sanitize message output'''
    message = message.replace('zonecfg: ', '')
    message = message.splitlines()
    for line in message:
        if line.startswith('On line'):
            message.remove(line)
    return "\n".join(message)