sample.xml

<dataflow projectname="Sum a b">
    <imports>
        <import module="basicmath" />
        <import module="io_module" />
    </imports>
    <entry-points>
        <entry-point id="7"/>
    </entry-points>
    <schema>
        <!-- Output IDs and Block IDs are unique across the project, however, blocks and outputs
             can share the same IDs -->
        <constructor id="1" module="basicmath" type="Integer" pos_x="0" pos_y="0">
            <output id="2" />
            <data>123</data>
        </constructor>
        <constructor id="3" module="basicmath" type="Integer" pos_x="0" pos_y="75">
            <output id="4" />
            <data>234</data>
        </constructor>
        <operation id="5" module="basicmath" name="AddIntegers" pos_x="200" pos_y="25">
            <!-- index defines the order of inputs in the operation -->
            <input index="0" output_id="2" />
            <input index="1" output_id="4" />
            <output id="6" />
        </operation>
        <operation id="7" module="io_module" name="PrintInteger" pos_x="400" pos_y="25">
            <input index="0" output_id="6" />
        </operation>
    </schema>
</dataflow>