POST https://people.googleapis.com/v1/contactGroups?prettyPrint=false
Host: people.googleapis.com
Content-Type: application/json

{
  "contactGroup": {
    "name": "test300",
    "clientData": [
      {
        "key": "Key one",
        "value": "Value one"
      }
    ]
  },
  "readGroupFields": "clientData,groupType,metadata,name"
}
