Static Class loading problem!

[abmmhasan]

How can I load a static class? Like I wanna use

use \Config;
Config::Value('TEST'); //Which will give a value of TEST

currently it giving following error

Fatal error:  Uncaught Error: Class 'Config' not found in ..\system.php:4
Stack trace:
#0 ..\index.php(4): require()
#1 {main}
  thrown in ..\system.php on line 4

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