.rtdb-security-rules-for-multi-access

{
  "rules": {
    "user_groups": {
      ".read": true, // public
    	".write": "root.child('user_groups/admins/users/' + auth.uid).exists()", // admins
      "members": {
        "users": {
          "$id": {
            ".write": "auth.uid === $id" // owner
          }
        }
      }
    },
    "users": {
      ".read": "root.child('user_groups/admins/users/' + auth.uid).exists()", // admins
    	".write": false,
      "$id": {
        ".read": "auth.uid === $id", // owner
        ".write": "auth.uid === $id" // owner
      }
    }
  }
}