code: def _check_realign(data):
      
      if "gatk4" not in data["algorithm"].get("tools_off", []) and not "gatk4" == data["algorithm"].get("tools_off"):
          if data["algorithm"].get("realign"):
              raise ValueError("In sample %s, realign specified but it is not supported for GATK4. "
                               "Realignment is generally not necessary for most variant callers." %
                               (dd.get_sample_name(data)))
docs: Check for realignment, which is not supported in GATK4