import yt

# Load the data file.
ds = yt.load("Sedov_3d/sedov_hdf5_chk_0002")

# Make a traditional slice plot.
sp = yt.SlicePlot(ds, "x", ("gas", "density"))

# Overlay the slice plot with thick red contours of density.
sp.annotate_contour(
    ("gas", "density"),
    levels=3,
    clim=(1e-2, 1e-1),
    label=True,
    plot_args={"colors": "red", "linewidths": 2},
)

# What about some nice temperature contours in blue?
sp.annotate_contour(
    ("gas", "temperature"),
    levels=3,
    clim=(1e-8, 1e-6),
    label=True,
    plot_args={"colors": "blue", "linewidths": 2},
)

# This is the plot object.
po = sp.plots[("gas", "density")]

# Turn off the colormap image, leaving just the contours.
po.axes.images[0].set_visible(False)

# Remove the colorbar and its label.
po.figure.delaxes(po.figure.axes[1])

# Save it and ask for a close fit to get rid of the space used by the colorbar.
sp.save(mpl_kwargs={"bbox_inches": "tight"})