const keys = Object.keys(item)
    let updateExpression = ""
    if (keys[0] ===  "ttl") {
      updateExpression = "SET #TTL = :" + String.fromCharCode(97 + 0)
    } else {
      updateExpression = "SET " + keys[0] + " = :" + String.fromCharCode(97 + 0)
    }
    for (let i = 1; i < keys.length; i++) {
      if (keys[i] ===  "ttl") {
        updateExpression = updateExpression + ", #TTL = :" + String.fromCharCode(97 + i)
      } else {
        updateExpression = updateExpression + ", " + keys[i] + " = :" + String.fromCharCode(97 + i)
      }
    }
    const expressionAttributeValuesDict = {}
    for (let i = 0; i < keys.length; i++) {
      expressionAttributeValuesDict[(":" + String.fromCharCode(97 + i))] = item[keys[i]]
    }
    const params = {
      TableName: getDynamoDBTableName(url),
      Key: {
        'Device_Browser_Version': {
          S: getDeviceBrowserVersionKey(device, browser, version),
        },
        'URL': {
          S: url,
        },
      },
      UpdateExpression: updateExpression,
      ExpressionAttributeValues: expressionAttributeValuesDict,
      ReturnValues: "ALL_NEW",
    }