/usergroups.list

{
    "ok": true,
    "usergroups": [
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            "date_create": 1446598059,
            "date_delete": 0,
            "date_update": 1446670362,
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            "description": "A group of all Administrators on your team.",
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            "id": "S0614TZR7",
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            "is_usergroup": true,
            "name": "Team Admins",
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                "groups": []
            },
            "team_id": "T060RNRCH",
            "updated_by": "U060RNRCZ",
            "user_count": "2"
        },
        {
            "auto_type": "owner",
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            "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"
        }
    ]
}