I had this problem too and solved it easily but it is a bug that needs to be fixed. For some reason ubot couldn't handle a "list from text" function unless it had 3 or more values.
I had 2 "items" seperated with a "," for example:
And I was getting the same error, to fix it all I did was add a 3rd useless item like this:
Hope the dev team can fix this little bug.