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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 make_application_private(application_id, sar_client=None):
 """ Set the application to be private. :param application_id: The Amazon Resource Name (ARN) of the application :type application_id: str :param sar_client: The boto3 client used to access SAR :type sar_client: boto3.client :raises ValueError """

    if not application_id:
        raise ValueError('Require application id to make the app private')

    if not sar_client:
        sar_client = boto3.client('serverlessrepo')

    sar_client.put_application_policy(
        ApplicationId=application_id,
        Statements=[]
    )