So i have these divs created from wordpress post and they have data attribute which is taken from php `<?php echo $rengdata->format('Y-m'); ?>`

```
<div class="renginiai-box">
     <div class="col-sm-3" data-renginiolaikas="2017-09"></div>
     <div class="col-sm-3" data-renginiolaikas="2017-09"></div>
     <div class="col-sm-3" data-renginiolaikas="2017-09"></div>
     <div class="col-sm-3" data-renginiolaikas="2017-10"></div>
</div>

```

What I need right now is to create one single button with unique date. Result should be like this.

```
<div class="laikotarpis">
      <button value="2017-09" class="laiko-btn">2017 09</button>
      <button value="2017-10" class="laiko-btn">2017 10</button>
</div>

```

I have no idea what function could fit this. Should I make array or there is a jQuery function for this