Vertex Group Weights in GreasePencilDrawing

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Hello,
Can anyone help me understand where the vertex group weights attributes are in the Grease Pencil API? I know 4.5 will have vertex_group_assign but I’m working with 4.4 and can’t get or set these weights anywhere. It’s not documented or in dir/help. Thank you!

import bpy

C       = bpy.context
frame   = C.object.data.layers.active.current_frame()
drawing = frame.drawing

def get_global_point_index(drawing, stroke_index, point_index):
    """
    Add the stroke’s curve_offset to the local point index
    so you end up with the unified “global” point index.
    """
    offset_value = drawing.curve_offsets[stroke_index].value
    return int(offset_value) + point_index

def get_bone_weight(drawing, bone_name, stroke_index, point_index):
    """
    Look up a FLOAT attribute by name on the point-domain,
    and return its .value (or 0.0 if it doesn’t exist).
    """
    global_idx = get_global_point_index(drawing, stroke_index, point_index)
    attr = drawing.attributes.get(bone_name)
    if not attr:
        return 0.0
    return attr.data[global_idx].value

# now loop and print
for stroke_idx, stroke in enumerate(drawing.strokes):
    for pt_idx, pt in enumerate(stroke.points):
        w0 = get_bone_weight(drawing, "Bone",     stroke_idx, pt_idx)
        w1 = get_bone_weight(drawing, "Bone.001", stroke_idx, pt_idx)
        print(f"Stroke {stroke_idx:2d}, Pt {pt_idx:2d} → Bone = {w0:.4f}, Bone.001 = {w1:.4f}")

The vertex group weights for “Bone” and “Bone.001” show in the Spreadsheet for the Control Points, but don’t show any values with my script.

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image1832×1168 101 KB

Thank you!