title: How to get GMT timeoffset value for current time in Dart/Flutter
body: <p>I'm developing an application where I need to get only GMT offset time, i.e. for India +5.30. How do I achieve this dart. </p>
  
  <p>var now = new DateTime.now();
    var timezoneOffset=now.timeZoneOffset;</p>
  
  <p>print (timezoneOffset);
  console : 05:30:00</p>
  
  <p>how to get +/- GMT offset?</p>