2.1.6 Sympy

A grade: { 11, 16, 22 }

B grade: { 8, 14, 17, 18, 23, 24 }

C grade: { }

F grade: { 1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 13, 15, 19, 20, 21 }