code: def assureSingleInstanceName(name):
      # if the name is known, it is not a group
      if name in name2label:
          return name
      # test if the name actually denotes a group
      if not name.endswith("group"):
          return None
      # remove group
      name = name[: -len("group")]
      # test if the new name exists
      if not name in name2label:
          return None
      # test if the new name denotes a label that actually has instances
      if not name2label[name].hasInstances:
          return None
      # all good then
      return name
  
label_desc: Use image node_id 1 for calling a global function with example usage: assureSingleInstanceName(name) and returns: name, name, None, None, None