def update_notification(AccountId=None, BudgetName=None, OldNotification=
    None, NewNotification=None):
    """
    Update the information about a notification already created
    See also: AWS API Documentation
    
    
    :example: response = client.update_notification(
        AccountId='string',
        BudgetName='string',
        OldNotification={
            'NotificationType': 'ACTUAL'|'FORECASTED',
            'ComparisonOperator': 'GREATER_THAN'|'LESS_THAN'|'EQUAL_TO',
            'Threshold': 123.0
        },
        NewNotification={
            'NotificationType': 'ACTUAL'|'FORECASTED',
            'ComparisonOperator': 'GREATER_THAN'|'LESS_THAN'|'EQUAL_TO',
            'Threshold': 123.0
        }
    )
    
    
    :type AccountId: string
    :param AccountId: [REQUIRED] Account Id of the customer. It should be a 12 digit number.

    :type BudgetName: string
    :param BudgetName: [REQUIRED] A string represents the budget name. No ':' character is allowed.

    :type OldNotification: dict
    :param OldNotification: [REQUIRED] Notification model. Each budget may contain multiple notifications with different settings.
            NotificationType (string) -- [REQUIRED] The type of a notification. It should be ACTUAL or FORECASTED.
            ComparisonOperator (string) -- [REQUIRED] The comparison operator of a notification. Currently we support less than, equal to and greater than.
            Threshold (float) -- [REQUIRED] The threshold of the a notification. It should be a number between 0 and 100.
            

    :type NewNotification: dict
    :param NewNotification: [REQUIRED] Notification model. Each budget may contain multiple notifications with different settings.
            NotificationType (string) -- [REQUIRED] The type of a notification. It should be ACTUAL or FORECASTED.
            ComparisonOperator (string) -- [REQUIRED] The comparison operator of a notification. Currently we support less than, equal to and greater than.
            Threshold (float) -- [REQUIRED] The threshold of the a notification. It should be a number between 0 and 100.
            

    :rtype: dict
    :return: {}
    
    
    :returns: 
    (dict) -- Response of UpdateNotification
    
    """
    pass
