Object.keys = Object.keys || function(o) {
    var result = [];
    for(var name in o) {
        if (o.hasOwnProperty(name))
          result.push(name);
    }
    return result;
};
function isdefined(v){return (typeof(window[v])!="undefined");}
function bind_toggle(div_name, prefix){
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}
function _toggle_div(div_id,prefix){
    $('#'+prefix+div_id).toggle("normal");
    $('#'+div_id+'-img-up').toggle();
    $('#'+div_id+'-img-down').toggle();
}