How to draw geometrical figures with coordinate axes

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Like this:

from sage.plot.plot3d.plot3d import axes
g = sphere(opacity=0.8)
show(g + axes(scale=1.5, radius=0.5, color='red'), viewer='threejs')

Note that if you don't want the bounding box (frame) to be drawn, you can do

show(g + axes(scale=1.5, radius=0.5, color='red'), frame=False, viewer='threejs')

For more details on the function axes, see the documentation here.