Suppress tooltips in Pygal charts

[Roy Hann]

Following up on Elijah's suggestion responding to my earlier question
about drawing gauges in a mobile (i.e. not normally internet connected)
application on a Raspberry Pi I am using Pygal and rendering to SVG.

I have found no way to stop Pygal from generating SVG that
downloads and invokes JavaScript for various roll-over effects like
tooltips.

Happily the requests to download JS fail fast and silent when there is
no network connection so it is sorta-kinda usable. I am worried
however about when I do have a mobile data connection enabled. I don't
need the tooltips and I don't want the risk of mobile data charges.

Is there any way to tell Pygal not to generate references to on-line
resources?

Roy