skeletal_styled.py

# using the iterability of the layout to set widths 

for item in gui.t_buttons:
    item.width = 256
    
for item in gui.r_buttons.row:
    item.width = 85
item.width = 256  # the last item is gui.r_buttons.row itself
item.columnWidth3 = (85,85,85)  # ditto
    
for item in gui.g_buttons.grid:
    item.width = 128
item.width = 256  # now the last item is the grid
item.cellWidth = 128   

cmds.showWindow(window)