投资组合方差计算

def solve(____):
    n = len(____)
    portfolio_variance = ____
    for i in range(____):
        portfolio_variance += weights[i] ** ____ * variances[i]
        for j in range(____):
            portfolio_variance += ____ * weights[i] * weights[j] * covariances[i][j]
    return round(____)