Grid#set_cell_size is missing

Why is there no Grid#set_cell_size method? I want to create cells
spanning several rows/columns. I get a method_missing error and it’s not
on the docs.

require ‘wx’

class GridFrame < Wx::Frame
def initialize
super(nil, -1, “Grid Cell Size”)

grid = Wx::Grid.new(self, -1)
grid.create_grid(10, 10)
grid.set_cell_size(1,1, 2, 2)

sizer = Wx::BoxSizer.new(Wx::VERTICAL)
sizer.add(grid)
set_sizer(sizer)

end
end

class GridCellSizeApp < Wx::App
def on_init
frame = GridFrame.new
frame.show
end
end

GridCellSizeApp.new.main_loop