Algorithme en python de transvection de matrice

def transvection(A,i,j,mu):
    B = recopiemat(A)

    "on fait B[i]=mu*A[i]"
    for b in range(len(A[i])):
        T= mu*A[j][b]+A[i][b]
        print(T)

        B[i][b] = mu*A[j][b]+A[i][i]

    return B