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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 text_bounding_box(self, size_pt, text):
 """ Return the bounding box of the given text at the given font size. :param int size_pt: the font size in points :param string text: the text :rtype: tuple (width, height) """

        if size_pt == 12:
            mult = {"h": 9, "w_digit": 5, "w_space": 2}
        elif size_pt == 18:
            mult = {"h": 14, "w_digit": 9, "w_space": 2}
        num_chars = len(text)
        return (num_chars * mult["w_digit"] + (num_chars - 1) * mult["w_space"] + 1, mult["h"])