D3.js drawing nodes and links from json structure

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    <title>tags</title>
    <script type="text/javascript" src="jquery.min.js"></script>      
    <script type="text/javascript" src="d3.v2.min.js"></script>
    
    
    <script type="text/javascript">
    $(document).ready(function() {
      $(window).resize(function() {$('.resizable').resize(); })
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    </script>   
    
    <style type="text/css">
      circle.node {
        stroke: #fff;
        stroke-width: 1.5px;
      }
      line.link {
        stroke: #999;
        stroke-opacity: .6;
      }
    </style>
    
  </head>
<body>

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