[
  {
    "op": "core/column-addition",
    "engineConfig": {
      "facets": [],
      "mode": "record-based"
    },
    "baseColumnName": "M|ISBN",
    "expression": "grel:[ forNonBlank(cells['M|ISBN'].value,v,if(isNumeric(v[0]),v,null),null), forNonBlank(cells['M|ISBN2'].value,v,if(isNumeric(v[0]),v,null),null) ].uniques().join('␟').replace('-','').toUppercase()",
    "onError": "set-to-blank",
    "newColumnName": "2000",
    "columnInsertIndex": 3
  }
]