PYTHON

A certain CS professor gives 100-point tests that are graded on the scale 90-100:A, 80-89:B, 70-79:C, 60-69:D, <60:F. Write a program that accepts a list of test scores, introduced one by one, as input and uses a decision structure to calculate and print the corresponding grade. The program will stop asking for more integers when the user presses ENTER .(this is the part I don't know how to include in the programme)

Input: 15 , 60 , ENTER

Out: F, D