d3_peter2.html

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  <rect width="80" height="60" fill="#eee"/>
  <text font-size="5px" x="3" y="8" id="item">Hello Rohit</text>
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    console.log(svg);
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    var y = parseFloat(el.getAttributeNS(null, 'y'));
    console.log(y);
    el.setAttributeNS(null, 'y', y+8);
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</svg>