'Change the font used by this widget. If font is None, the current
font is used.'

def cmd_set_font(self, font=UNSPECIFIED, fontsize=UNSPECIFIED, fontshadow=UNSPECIFIED):

    if (font is not UNSPECIFIED):
        self.font = font
    if (fontsize is not UNSPECIFIED):
        self.fontsize = fontsize
    if (fontshadow is not UNSPECIFIED):
        self.fontshadow = fontshadow
    self.bar.draw()
