def check_speed_button_surfs(self):
        """Highlight/unhighlighted speed button surfaces.

        If the current speed correspond to the speed set by
        an specific button, that button is highlighted, otherwise
        it is unhighlighted.
        """
        ### get current speed
        current_speed = self.speed_entry.get()

        ### reassign surfaces to each button, depending on whether
        ### their respective speed matches the current one

        for speed, button in SPEED_TO_BUTTON.items():

            index = 1 if current_speed == speed else 0
            button.image = SPEED_BUTTON_SURF_MAP[button][index]
Highlight/unhighlighted speed button surfaces.

        If the current speed correspond to the speed set by
        an specific button, that button is highlighted, otherwise
        it is unhighlighted.
        
nodezator/editing/playback/play.py