Finally

gistfile1.html

<script>
    
  //KEYBOARD NAVIGATION FOR PERMALINK
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        if (e == null) {
            keycode = event.keyCode;
        } else {
            keycode = e.which;
        }
        if(keycode == 39){
            $('#sb-site').addClass( "leftAnimate" ); //this class will animate the element to the left
            setTimeout(function(){
                window.location = $('#nextPost').attr('href');
            },300);
        } else if(keycode == 37){
            $('#sb-site').addClass( "rightAnimate" ); /this class will animate the element to the right
            setTimeout(function(){
                window.location = $('#previousPost').attr('href');
            },300);
        }   
        else if(keycode == 191){
            $("#sb-site").addClass( "fadeAnimate" );
            setTimeout(function(){
                window.location = $('#random').attr('href');
            },300);
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    };

</script>