[j0hnik]

<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
	<a id="cat_3" href="#" class="opacity_filter checkshadow3 isExcept" onclick="return false">
		<img src="put/put2/put3/vase.svg" class="a_check my-1 graycategory" title="Категория 3" height="48">
	</a>
	<script>
		$('.checkshadow3').click(function() {
			var th = $(this), child = th.children();

			if(th.is('.check')){
				th.removeClass('check');
				child.attr('src', child.attr('src').replace(/(\w+)_a(\.\w+)/, '$1'+'$2'));
			}
			else{
				th.addClass('check');
				child.attr('src', child.attr('src').replace(/(\w+)(\.\w+)/, '$1'+'_a'+'$2'));
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