How to use the ttkwidgets.color.functions.rgb_to_hsv function in ttkwidgets

def test_rgb_to_hsv(self):
        self.assertEqual(tkf.rgb_to_hsv(255, 0, 0), (0, 100, 100))

self.saturation.set(s)
            self.value.set(v)
            self.bar.set(h)
            self.square.set_hsv((h, s, v))
            if self.alpha_channel:
                a = self.alpha.get()
                self.hexa.insert('end', ("%2.2x" % a).upper())
                self.alphabar.set_color((r, g, b, a))
        elif self.alpha_channel and re.match(r"^#[0-9A-F]{8}$", color):
            r, g, b, a = hexa_to_rgb(color)
            self.red.set(r)
            self.green.set(g)
            self.blue.set(b)
            self.alpha.set(a)
            self.alphabar.set_color((r, g, b, a))
            h, s, v = rgb_to_hsv(r, g, b)
            self.hue.set(h)
            self.saturation.set(s)
            self.value.set(v)
            self.bar.set(h)
            self.square.set_hsv((h, s, v))
        else:
            self._update_color_rgb()
        self._update_preview()

"""Respond to user click on a palette item."""
        label = event.widget
        label.master.focus_set()
        label.master.configure(relief="sunken")
        r, g, b = self.winfo_rgb(label.cget("background"))
        r = round2(r * 255 / 65535)
        g = round2(g * 255 / 65535)
        b = round2(b * 255 / 65535)
        args = (r, g, b)
        if self.alpha_channel:
            a = self.alpha.get()
#            a = self.get_color_value(self.alpha)
            args += (a,)
            self.alphabar.set_color(args)
        color = rgb_to_hexa(*args)
        h, s, v = rgb_to_hsv(r, g, b)
        self.red.set(r)
        self.green.set(g)
        self.blue.set(b)
        self.hue.set(h)
        self.saturation.set(s)
        self.value.set(v)
        self.hexa.delete(0, "end")
        self.hexa.insert(0, color.upper())
        self.bar.set(h)
        self.square.set_hsv((h, s, v))
        self._update_preview()

def _update_color_rgb(self, event=None):
        """Update display after a change in the RGB spinboxes."""
        if event is None or event.widget.old_value != event.widget.get():
            r = self.red.get()
            g = self.green.get()
            b = self.blue.get()
            h, s, v = rgb_to_hsv(r, g, b)
            self.hue.set(h)
            self.saturation.set(s)
            self.value.set(v)
            args = (r, g, b)
            if self.alpha_channel:
                args += (self.alpha.get(),)
                self.alphabar.set_color(args)
            hexa = rgb_to_hexa(*args)
            self.hexa.delete(0, "end")
            self.hexa.insert(0, hexa)
            self.square.set_hsv((h, s, v))
            self.bar.set(h)
            self._update_preview()

bg = create_checkered_image(width, height)
        r, g, b = color
        w = width - 1.
        gradient = Image.new("RGBA", (width, height))
        for i in range(width):
            for j in range(height):
                gradient.putpixel((i, j), (r, g, b, round2(i / w * 255)))
        self.gradient = ImageTk.PhotoImage(Image.alpha_composite(bg, gradient),
                                           master=self)

        self.create_image(0, 0, anchor="nw", tags="gardient",
                          image=self.gradient)
        self.lower("gradient")

        x = alpha / 255. * width
        h, s, v = rgb_to_hsv(r, g, b)
        if v < 50:
            fill = "gray80"
        else:
            fill = 'black'
        self.create_line(x, 0, x, height, width=2, tags='cursor', fill=fill)

color += (255,)
                    self._old_alpha = 255
                else:
                    self._old_alpha = color[3]
            old_color = rgb_to_hexa(*color)

        # --- GradientBar
        hue = col2hue(*self._old_color)
        bar = ttk.Frame(self, borderwidth=2, relief='groove')
        self.bar = GradientBar(bar, hue=hue, width=200, highlightthickness=0)
        self.bar.pack()

        # --- ColorSquare
        square = ttk.Frame(self, borderwidth=2, relief='groove')
        self.square = ColorSquare(square, hue=hue, width=200, height=200,
                                  color=rgb_to_hsv(*self._old_color),
                                  highlightthickness=0)
        self.square.pack()

        frame = ttk.Frame(self)
        frame.columnconfigure(1, weight=1)
        frame.rowconfigure(1, weight=1)

        # --- color preview: initial color and currently selected color side by side
        preview_frame = ttk.Frame(frame, relief="groove", borderwidth=2)
        preview_frame.grid(row=0, column=0, sticky="nw", pady=2)
        if alpha:
            self._transparent_bg = create_checkered_image(42, 32)
            transparent_bg_old = create_checkered_image(42, 32,
                                                        (100, 100, 100, 255),
                                                        (154, 154, 154, 255))
            prev_old = overlay(transparent_bg_old, hexa_to_rgb(old_color))

def set_rgb(self, sel_color):
        """
        Put cursor on sel_color given in RGB.

        :param sel_color: color in RBG format
        :type sel_color: sequence(int)
        """
        width = self.winfo_width()
        height = self.winfo_height()
        h, s, v = rgb_to_hsv(*sel_color)
        self.set_hue(h)
        x = v / 100.
        y = (1 - s / 100.)
        self.coords('cross_h', 0, y * height, width, y * height)
        self.coords('cross_v', x * width, 0, x * width, height)