Copy Wrkset Name into a Parameter

how can i take from a list the characters between the comas??
i need to take from that list only the info to paste it into a parameter in Revit.

what i try to do is to copy the workset of each element into a text parameter.
image

If i read your title correctly you want to seperate the actual name of the workset for further use?
If by commas you mean quotation marks than this works fine:
image

If you need to remove the quotation marks from that workset name you showed:

Edit:

I am just now realising your list does not seem tocontain elements, could you show the rest of your graph?
You could also do this:

Looks like the elements were converted to strings. As @Garbage_Collector said, you just need to use Element.Name on the actual element object.