How can three different spellings of the same date all parse into one subtractable object, and which dictionary does `cal_per_hr` live in?
Short drills on what this video just taught. Write the code, run the checks, and reveal the answer only if you are stuck.
The two datetime objects start_date (September 30, 2021 at 1:35 PM) and end_date (1:45 PM the same afternoon) are already built for you — exactly what parser.parse hands back. Work out how long that stretch of time is and assign the result to gap.
from datetime import datetime # parser.parse would hand back exactly these two objects start_date = datetime(2021, 9, 30, 13, 35) end_date = datetime(2021, 9, 30, 13, 45)