9. Consider the following Python program: x = 1; y = 3; z = 5; subi(): a = 7; y = 9; z = 11; def sub2(): global x; a = 13; x = 15; w = 17; List all the variables, along with the program units where they are declared (e.g., global y, or local y of sub1), that are visible in the bodies of subi, sub2, and sub3 (pointed as 1, 2, 3) assuming static scoping is def sub3(): nonlocal a; a = 19; b = 21; z = 23; used