def METHOD_NAME(n):
    xv = np.random.rand(n, n)
    yv = np.random.rand(n, n)
    theta = np.arccos(1 - 2 * xv)
    phi = 2.0 * math.pi * yv
    phi = phi.reshape(-1)
    theta = theta.reshape(-1)
    vx = -np.sin(theta) * np.cos(phi)
    vy = -np.sin(theta) * np.sin(phi)
    vz = np.cos(theta)
    return np.stack([vx, vy, vz], 1), phi, theta