How does the FrameAnimation3d class work in Ursina (a message to pokepetter)

I have been doing some developing with the ursina engine but I wanted to ad some animations to my 3d models. However I noticed after scouring the internet that no one has written any code using the FrameAnimation3d class and there are no samples files using it. Does any one out there no to to import 3d animations into ursina.