C2_W1_Assignment 'name 'prices_A' is not defined'

[TMosh]

You can get a new copy and start over on the assignment.
See the “Topic 1b” item in the M4ML FAQ:

Math for Machine Learning FAQ

TOPIC 1a HOW TO GET A FRESH OR LATEST VERSION OF A NOTEBOOK These steps are tried and tested Click file, then select open. You will find all the files related to the assignment. Here if you have saved a copy of your notebook with renaming other than what was mentioned. Then go ahead and delete the assignment notebook by selecting the particular notebook. Once deleted, you will find 404 not found image on your browser. Then close the browser. Open the assignment page again, …