title: Unable to correctly call google cloud identity apis
body: <p>Hi I'm trying to use google cloud identity apis in order to retrieve the list of users registered with CI under my organization. I've tried first with this api <a href="https://cloud.google.com/identity/docs/reference/rest/v1/groups/list" rel="nofollow noreferrer">https://cloud.google.com/identity/docs/reference/rest/v1/groups/list</a> passing the organization ID as parent field but I got the following error:</p>
  
  <pre><code>{
    "error": {
      "code": 400,
      "message": "Request contains an invalid argument.",
      "status": "INVALID_ARGUMENT"
    }
  }
  </code></pre>
  
  <p>I've also tried with <a href="https://cloud.google.com/identity/docs/reference/rest/v1/groups/get" rel="nofollow noreferrer">https://cloud.google.com/identity/docs/reference/rest/v1/groups/get</a> passing "groups/" as name but this time I got this output:</p>
  
  <pre><code>{
    "error": {
      "code": 403,
      "message": "Error(2017): User does not have permission to get group 'groups/abcpi1tg3uve2ab' (or it may not exist).",
      "status": "PERMISSION_DENIED",
      "details": [
        {
          "@type": "type.googleapis.com/google.rpc.ResourceInfo",
          "resourceType": "cloudidentity.googleapis.com/Group",
          "resourceName": "groups/abcpi1tg3uve2ab",
          "owner": "domain:cloudidentity.googleapis.com",
          "description": "Error(2017): User does not have permission to get group 'groups/abcpi1tg3uve2ab' (or it may not exist)."
        }
      ]
    }
  }
  </code></pre>
  
  <p>and I'm using the same account I use to log into Admin console. 
  I'm testing the apis via apis explorer with a superadmin user.
  Can anyone please tell me what I'm doing wrong and what the "parent" required field exactly mean in the first api?</p>