Checking Symmetry by the Secondary Diagonal for a 2-D Matrix

def symmetryBySecDiag(matrix):
    newmat = [matrix[i] for i in range(-1, -(len(matrix))-1, -1)]
    res = []

    for i in range(len(newmat)):
        temp = []

        for j in range(len(newmat[i])):
            temp.append(newmat[j][i])

        res.append(temp)

    return True if res == newmat else False

print(symmetryBySecDiag([[0,0,1], [0,1,0], [1,0,0]]))