string @primpath; 

// Debugging message for variable definition
printf("Variables defined.");

// Retrieve variants
string models[] = usd_variants(0, @primpath, "model");

// Debugging message to check if variants are retrieved
printf("Number of variants: %d", len(models));

// Check if at least one variant is available
if (len(models) > 0) {
    // Set the desired variant
    usd_setvariantselection(0, @primpath, "model", models[1]);

    // Debugging message for variant selection
    printf("Variant selection set.");

    // Apply API to the variant
    usd_applyapi(0, @primpath, "GeomModelAPI");

    // Debugging message for API application
    printf("API applied.");
} else {
    // Debugging message if no variants are available
    printf("No variants available.");
}

from pxr import UsdGeom

try:
    lopNode = hou.pwd().inputs()[0]
    stage = lopNode.stage()
    print(stage)

    node_base = "/instanced_variants1/Instance"
    variable_value = hou.node(".").parm("primnr").eval()
    node_base += str(variable_value)

    prim = stage.GetPrimAtPath(node_base)
    
    testing = prim.GetAttribute("primvars:TESTING").Get()
    
    
    pvAPI = UsdGeom.PrimvarsAPI(prim)
    primvar = pvAPI.FindPrimvarWithInheritance("TESTING")
    primvarValue = primvar.ComputeFlattened()
    return testing


except Exception as e:

    return 2