         <a class="portfolio-link" href="../graph/donut_basic.html">
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                <div class="portfolio-hover-content">
                  <p>Basic donut chart</p>
                  <hr />
                  <p class="explanation_portfolio">
                    The most basic donut chart you can do in d3.js. Keeping only
                    the core code.
                  </p>
                </div>
              </div>
              <img
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