How to make a label text bold with code?

Godot Version

4.2.1

Question

simple question. I created a label with code and want to keep everything the same… but make the font bold.
I tried playing with font in the theme but cant find option to make font bold.
I tried creating a new system font and setting weight to 700 (bold) but still nothing…
I dont want to upload a custom font file or make major changes. I want to use the same default font as usual… just make it a bit bolder!

here is my come so far…

var labelStyle = StyleBoxFlat.new();
labelStyle.bg_color = Color(0.25, 0.26, 0.30, 1.0);
labelStyle.set_content_margin_all( 4.0 );

var label = Label.new()
label.text = "some text"
label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER

label.add_theme_stylebox_override("normal",labelStyle);
var font  = SystemFont.new();
font.font_weight = 700;
label.add_theme_font_override("font", font);

your_label_node.add_theme_constant_override("outline_size",10)