/usergroups.list

{
  "ok": true,
  "usergroups": [
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      "date_create": 1446598059,
      "date_delete": 0,
      "date_update": 1446670362,
      "deleted_by": null,
      "description": "A group of all Administrators on your team.",
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      "id": "S0614TZR7",
      "is_external": false,
      "is_usergroup": true,
      "name": "Team Admins",
      "prefs": {
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        "groups": []
      },
      "team_id": "T060RNRCH",
      "updated_by": "U060RNRCZ",
      "user_count": "2"
    },
    {
      "auto_type": "owner",
      "created_by": "USLACKBOT",
      "date_create": 1446678371,
      "date_delete": 0,
      "date_update": 1446678371,
      "deleted_by": null,
      "description": "A group of all Owners on your team.",
      "handle": "owners",
      "id": "S06158AV7",
      "is_external": false,
      "is_usergroup": true,
      "name": "Team Owners",
      "prefs": {
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      },
      "team_id": "T060RNRCH",
      "updated_by": "USLACKBOT",
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    },
    {
      "auto_type": null,
      "created_by": "U060RNRCZ",
      "date_create": 1446746793,
      "date_delete": 1446748865,
      "date_update": 1446747767,
      "deleted_by": null,
      "description": "Marketing gurus, PR experts and product advocates.",
      "handle": "marketing-team",
      "id": "S0615G0KT",
      "is_external": false,
      "is_usergroup": true,
      "name": "Marketing Team",
      "prefs": {
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        "groups": []
      },
      "team_id": "T060RNRCH",
      "updated_by": "U060RNRCZ",
      "user_count": "0"
    }
  ]
}