How to create a GUID autonumber field with DAO

The problem that once you create field with dbGUID type, and assign a default value to it as GenGUID() it starts working, but on new row it shows "#Name". The trick is to set dbSystemField attribute flag for this field, then "#Name" will gone.
Here a procedure which Access MVP John Spencer build to demonstrate this:

Sub BuildGUIDAutonumber()
'Test Procedure

Dim dbany As DAO.Database
Dim tdefAny As DAO.TableDef
Dim fldAny As DAO.Field
   Set dbany = CurrentDb()
   On Error Resume Next
   dbany.TableDefs.Delete "A__A"
   On Error GoTo 0
   dbany.TableDefs.Refresh
  
   Set tdefAny = dbany.CreateTableDef("A__A")
   With tdefAny
      Set fldAny = .CreateField("GUIDFld", dbGUID)
      fldAny.Attributes = fldAny.Attributes Or dbSystemField
      fldAny.Type = dbGUID
      fldAny.Properties("DefaultValue") = "GenGUID()"
      .Fields.Append fldAny
   End With
   dbany.TableDefs.Append tdefAny
   dbany.TableDefs.Refresh
End Sub