<svg width="8cm" height="4cm" viewBox="0 0 800 400" version="1.1">      <desc>Example radgrad01 - fill a rectangle by referencing a radial gradient paint server</desc>      <g>           <defs>                <radialGradient id="MyGradient" gradientUnits="userSpaceOnUse" cx="400" cy="200" r="300" fx="400" fy="200">                     <stop offset="0%" stop-color="red"/>                     <stop offset="50%" stop-color="blue"/>                     <stop offset="100%" stop-color="red"/>                </radialGradient>           </defs>           <rect fill="none" stroke="blue" x="1" y="1" width="798" height="398"/>           <rect fill="url(#MyGradient)" stroke="black" stroke-width="5" x="100" y="100" width="600" height="200"/>      </g> </svg>

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