public override JwtHeader CreateHeader(string signingKeyPath)
 {
     using (RSA rsaKey = RSA.Create())
     {
         var xmlKey = File.ReadAllText(signingKeyPath);
         rsaKey.CustFromXmlString(xmlKey);
         var signingKey         = new RsaSecurityKey(rsaKey);
         var signingCredentials = new SigningCredentials(signingKey, SecurityAlgorithms.RsaSha256);
         return(new JwtHeader(signingCredentials));
     }
 }