On-behalf-of flow - How to Call OBO section example is missing "BuildConfidentialClientApplication()" method implementation

[pirahawk]

On the On-behalf-of flows with MSAL.NET, the section titled "How to call OBO" has an example

private async Task AddAccountToCacheFromJwt(IEnumerable<string> scopes, JwtSecurityToken jwtToken, ClaimsPrincipal principal, HttpContext httpContext)
{
  if (jwtToken == null)
  {
    throw new ArgumentOutOfRangeException("tokenValidationContext.SecurityToken should be a JWT Token");
  }
  UserAssertion userAssertion = new UserAssertion(jwtToken.RawData, "urn:ietf:params:oauth:grant-type:jwt-bearer");
  IEnumerable<string> requestedScopes = scopes ?? jwtToken.Audiences.Select(a => $"{a}/.default");

  // Create the application
  var application = BuildConfidentialClientApplication(httpContext, principal);

  // await to make sure that the cache is filled in before the controller tries to get access tokens
  var result = await application.AcquireTokenOnBehalfOf(requestedScopes, userAssertion).ExecuteAsync();                     
}

It looks like the method implementation for BuildConfidentialClientApplication in the example on the page is missing?