title: Convert API timezone in seconds to GMT timezone. Also convert API temperature to deg celcius
body: <p>I am getting API weather data from some weather website. 
  It has provided me timezone as 19800 which I want to convert to GMT + 05:30 but I am not able to do the same.</p>
  
  <p>Also it has given temperatures as 297.58 which I want to convert to deg Celcius.</p>
  
  <p>I tried assuming that given temperature as deg Kelvin and reducing 273 from it but it is not working</p>
  
  <p>I want to be able to convert seconds to time zone and show temp in degree celcius.</p>