<svg width="51px" height="50px" viewBox="0 0 51 50">

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        <animate attributeName="height" values="50;10;50" begin="0s" dur="1s" repeatCount="indefinite" />
    </rect>

    <rect x="19" y="0" width="13" height="50" fill="#12d8fa">
        <animate attributeName="height" values="50;10;50" begin="0.2s" dur="1s" repeatCount="indefinite" />
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    <rect x="38" y="0" width="13" height="50" fill="#06ffcb">
        <animate attributeName="height" values="50;10;50" begin="0.4s" dur="1s" repeatCount="indefinite" />
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</svg>
body {
  background: #f2f2f2;
}

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