<!DOCTYPE html>
<html>
<body>
<svg xmlns="http://www.w3.org/2000/svg" width="350">
<defs>
<clipPath id="clip1">
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</clipPath>
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    <rect width="200" height="200"/>
</clipPath>
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<g>
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    <circle cx="100" cy="100" r="50" fill="red"  opacity=".5" />
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</g>
<g transform="translate(200,0)">
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</g>
</svg>
</body>
</html>