Hi 365datascience, 
 
First of all, thank you for making the coursework material available through April 15. I am aware the video lectures are not made available, but the notes are consistently available via a download button, which made me think this may be a missing link.
The lecture is from the “Time Series Analysis in Python”, on section “Arch Model”, specifically “The arch_model Method”: https://365datascience.teachable.com/courses/666338/lectures/11892834
Normally the download button is available below each note, but in this case “arch_model.pdf” contains no button!