<svg width='400' height='400' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' >
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        <symbol id="symbol-1">
            <rect width='50' height='50' fill='skyblue'/>
            <rect x='5' y='5' width='40' height='40' fill='green'/>
        </symbol>
        <pattern id='pattern-1' width='50' height='50' patternUnits='userSpaceOnUse'>
            <use width='50' height='50' xlink:href='#symbol-1' />
        </pattern>
        <pattern id='pattern-2' x='0' y='0' width='0.25' height='0.25' patternUnits='objectBoundingBox'>
            <use width='50' height='50' xlink:href='#symbol-1' />
        </pattern>
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    <rect x='0' y='0' width='200' height='200' fill='url(#pattern-1)'/>
    <line x1='200' y1='100' x2='400' y2='100' stroke-width='200' stroke='url(#pattern-1)'/>
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    <!-- This line won't be drawn since pattern-2 has 'objectBoundingBox' and the line box is empty -->
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</svg>