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<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item>
        <shape android:innerRadius="0dp"
            android:shape="ring"
            android:thickness="3dp"
            android:useLevel="false" >
            <solid android:color="@color/gray" />
        </shape>
    </item>
</layer-list>