def setCardsAggregationMode(connection, chassisChainUrl, chassisIp, cardIdList, mode):
    '''
        This method is used to change the aggregation mode on a list of cards from a chassis. In order to call this method, the desired chassis must be already  added and connected.

        Args:
        - connection is the connection object that manages the HTTP data transfers between the client and the REST API
        - chassisChainUrl is the address of the chassisChain resource
        - chassisIp is the IP or hostname of the chassis that contains the card(s)
        - cardIdList is a list of card IDs
        - mode is the aggregation mode that will be set on the cards. Possible options are (depending on card type): NA (Non Aggregated), 1G, 10G, 40G
    '''
    setCardsAggregationModeOperationUrl = "%s/operations/setCardsAggregationMode" % chassisChainUrl
    cardIdStr = ",".join([str(cardId) for cardId in cardIdList])

    data = {"chassisIp":chassisIp, "cardIdList":cardIdStr, "mode":mode}

    performGenericOperation(connection, setCardsAggregationModeOperationUrl, data)