from sympy import *
from spb import *
import k3d
var("x:z")
graphics(
    vector_field_3d(z, -x, y, (x, -3, 3), (y, -3, 3), (z, -3, 3),
        n=40, streamlines=True,
        stream_kw=dict(
            starts=True,
            npoints=400,
            width=0.025,
            color_map=k3d.colormaps.matplotlib_color_maps.viridis
        )
    ),
    backend=KB, xlabel="x", ylabel="y", zlabel="z")