def accuracy(self, matrix):
        """
        Average of lower triangle + diagonal
        Evaluate accuracy on seen tasks
        """
        r, _ = matrix.shape
        res = [matrix[i, j] for i in range(r) for j in range(i + 1)]
        return sum(res) / len(res)

        Average of lower triangle + diagonal
        Evaluate accuracy on seen tasks
        
avalanche/benchmarks/classic/clear.py