Как отобразить агрегированное значение суммы внутри круговой диаграммы другим цветом?

Я мог получить значение каждого бренда внутри круговой диаграммы, регулируя радиус, но я не мог изменить цвет, не сделав всю круговую диаграмму черной. Я считаю, что мне, возможно, придется преобразовать сумму каждого бренда, но получение правильного значения в правильной позиции, кажется, моей главной проблемой.

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