How to extract the frame rate of a source clip of a movie strip?

Question

I know the width and height of a source clip can be extracted with this: https://docs.blender.org/api/2.79/bpy.types.SequenceElement.html

Ex.:

bpy.context.scene.sequence_editor.active_strip.elements[0].orig_width
bpy.context.scene.sequence_editor.active_strip.elements[0].orig_height

But how do I get the fps of the source clip?