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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 convert_la_to_rgba(self, row, result):
 """Convert a grayscale image with alpha to RGBA."""

        for i in range(len(row) // 3):
            for j in range(3):
                result[(4 * i) + j] = row[2 * i]
            result[(4 * i) + 3] = row[(2 * i) + 1]