How do I select vertices by material slot in Python?

Question

I'm trying to collapse some items which have multiple material slots that are unneeded (and when exported come in as distinct materials, which I do not want). I have the code needed so far to recognize when a material slot shares the same image map (so a candidate to eliminate that slot) if only I can select it. It does select A material slot, but not all of them, and I'm pretty sure it's because I'm still confused about the way to specify what material slot I need.

Here's the code:

imageTextures = []
# Iterate over all of the imported object's material slots
for m in imported.material_slots:
    if m.material:
        # Iterate over all the current material's texture slots
        for t in m.material.texture_slots:
            # If this is an image texture, with an active image append its name to the list
            if t and t.texture.type == 'IMAGE' and t.texture.image:
                if t.texture.image.name not in imageTextures: 
                    imageTextures.append(t.texture.image.name)
                    print ("Image is ", t.texture.image.name)


# Go to Edit mode
bpy.ops.object.mode_set(mode='EDIT')
    for textureFile in imageTextures:
        print ("Our Textures are", textureFile) 
        # Deselect all the vertices
        bpy.ops.mesh.select_all(action='DESELECT')
            for m in imported.material_slots:
                if m.material:
                    # Iterate over all the current material's texture slots
                    for t in m.material.texture_slots:
                        if t and t.texture.type == 'IMAGE' and t.texture.image:
                            if t.texture.image.name == textureFile: 
                                # Select the vertices of the vertex group
                                print ("Selecting", m.material.name)
                                bpy.ops.object.material_slot_select()

So if someone could just correct me on that last part I'd be very grateful (after this I need to create a new mat slot and assign the selected verts to this, and then delete all the other mat slots, but I think I can handle those chores).

Answer 1

Okay, I figured it out (and I'm dumb and if there is a way to delete these questions you answer yourself I would).

All I had to do was to set the active index of the material and then do a material slot select (as I already had). So this works:

for num, m in enumerate(imported.material_slots):
    ...
    bpy.context.object.active_material_index = num
    bpy.ops.object.material_slot_select()

Now just to make a new material, assign the faces to it, and delete all the old ones, but I think I have that.