Making a string into a table.

I currently have a file, that is a saved TableToKeyValues. Here is the file:

	"1"		"weapon_pistol"

So when I import it:

local str = file.Read( databaseFolders( ply ) .. "items.dat", "DATA" )
local db = util.KeyValuesToTable( str )
PrintTable( db )

The PrintTable comes out with nil, whilst the print comes out correctly, as a string.
How do I make the str string into a table?