code: def _get_validate(data):
      
      if data.get("vrn_file") and tz.get_in(["config", "algorithm", "validate"], data):
          return utils.deepish_copy(data)
      elif "group_orig" in data:
          for sub in multi.get_orig_items(data):
              if "validate" in sub["config"]["algorithm"]:
                  sub_val = utils.deepish_copy(sub)
                  sub_val["vrn_file"] = data["vrn_file"]
                  return sub_val
      return None
docs: Retrieve items to validate, from single samples or from combined joint calls.