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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def normalized_rgb(self):
 r""" Returns a tuples of the normalized values of the red, green, and blue channels of the Colour. Returns: tuple: the rgb values of the colour (with values normalized between 0.0 and 1.0) .. note:: Uses the formula: \\[ r_{norm} = \\begin{cases} \\frac{r_{255}}{12.92}\\ \\qquad &\\text{if $r_{255}$ $\\le$ 0.03928} \\\\ \\left(\\frac{r_{255} + 0.055}{1.055}\\right)^{2.4} \\quad &\\text{otherwise} \\end{cases} \\] `Source <http://www.w3.org/TR/2008/REC-WCAG20-20081211/#relativeluminancedef>`_ """


        r1 = self._r / 255
        g1 = self._g / 255
        b1 = self._b / 255

        if r1 <= 0.03928:
            r2 = r1 / 12.92
        else:
            r2 = math.pow(((r1 + 0.055) / 1.055), 2.4)
        if g1 <= 0.03928:
            g2 = g1 / 12.92
        else:
            g2 = math.pow(((g1 + 0.055) / 1.055), 2.4)
        if b1 <= 0.03928:
            b2 = b1 / 12.92
        else:
            b2 = math.pow(((b1 + 0.055) / 1.055), 2.4)

        return (r2, g2, b2)