code: def abfFname_Load():
      
      fname=userFolder()+"/abfFname.ini"
      if os.path.exists(fname):
          abfFname=open(fname).read().strip()
          if os.path.exists(abfFname) or abfFname.endswith("_._"):
              return abfFname
      return os.path.abspath(os.sep)
docs: return the path of the last loaded ABF.