6👍
✅
Upper class is a term used mostly in U.S based colleges to collectively denote Juniors and Seniors ( i.e the 3rd and 4th year students in a college with usually 4 year degrees, Source), this clears why such function was needed in the first place.
The function will return True or False if the value of <instance-of-class-student>.year_in_school is equal to JR or SR
If the syntax used in the body of the function is unclear, here are some examples of membership operators: http://www.tutorialspoint.com/python/membership_operators_example.htm
Source:stackexchange.com