List of items where each item has a list of ten values

I want to replace the 10th value of item number 2 but I have no way of keeping track of where the item is in the list.   Right now i know its the 2nd item because that is the way my test is set up but in the real world when a user might be using my app I don't think I have a way of tracking it. Here Is my screen shot of what i've been trying but it does not work.  I am going crazy with this please help. How do I reference those 10 values

In case I understand your problem correctly, then try this:

first get the value of the tag you want to replace, in your example the value is a list of 10 items, then replace the 10th item of the list and store the value (i.e. the modified list) again in TinyDB