The doc name is formatted lname,fname. How do I replace the comma with a ^ so I get lname^fname.

I am trying to create a scheduled task but get not implemented error when I try to run it.

Class PICIS.Core.Tasks.CleanEntry Extends %RegisteredObject
{

ClassMethod ClearTasks(pBackupFile As %String = "d:\Temp\BackupTasks.xml", pDelete As %Boolean = 0)
{
    // Create backup file
    Set tBackup = ##class(%Stream.FileCharacter).%New()
    Set tBackup.Filename = pBackupFile
    Do tBackup.WriteLine("<?xml version=""1.0"" encoding=""UTF-8""?>")
    Do tBackup.WriteLine("<Tasks>")

    // Delete loop
    Set tCount = 0
    Set tSC = $$$OK
    Set tRS = ##class(%SQL.Statement).