mapnik/plugins/input/templates/helloworld/test.xml

<Map srs="+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs" background-color="white" minimum-version="0.7.2">
    <Style name="style">
        <Rule>
            <PointSymbolizer/>
            <!-- the hello world sample hardcodes 'key' as the hypothetical field name -->
            <TextSymbolizer name="[key]" size="10" dx="5" dy="5" face-name="DejaVu Sans Book"/>
            <LineSymbolizer stroke="green" stroke-width="3"/>
        </Rule>
    </Style>
    <!-- this example only works in EPSG:4326 -->
    <Layer name="test" srs="+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs">
        <StyleName>style</StyleName>
        <Datasource>
            <!-- here we create a 'hello' type datasource which simply
            displays a point in the middle of the world's boundin box -->
            <Parameter name="type">hello</Parameter>
        </Datasource>
    </Layer>
</Map>