Only valid input is "whatever"
must type "whatever"
{
  "whatever": [
    {
      "$validators": {},
      "$asyncValidators": {},
      "$parsers": [],
      "$formatters": [
        null
      ],
      "$viewChangeListeners": [],
      "$untouched": true,
      "$touched": false,
      "$pristine": true,
      "$dirty": false,
      "$valid": false,
      "$invalid": true,
      "$error": {
        "whatever": true
      },
      "$name": "userName",
      "$options": null
    }
  ]
}
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