title: From where to use TokenHelper class for client context in SharePoint Online?
body: <p>I have been reading several articles to get SharePoint Online client context with the generated access token. All of them use <code>TokenHelper</code> class to get the client context as shown below:</p>
  
  <pre><code>ClientContext clientContext = TokenHelper.GetClientContextWithAccessToken(targetWeb, AccessToken);
  </code></pre>
  
  <p>My question is how do we access <code>TokenHelper</code> class? I could not find it in the reference <code>Microsoft.SharePoint.Client</code> version 16.1.0.0. What reference do we need to add to access this class?</p>