Activity 3

Naming values in Python is a very powerful tool. It allows you to create code that is more readable and more reusable. It also introduces a level of complexity that can make creating programs difficult if you do not understand Python's underlying memory system. This activity will explore how Python variable references affect your programs.

 1: a = 1
 2: b = a
 3: c = a + b
 4: print('a =', a)
 5: print('b =', b)
 6: print('c =', c)
 7: a = 2
 8: print('a =', a)
 9: print('b =', b)
10: print('c =', c)

1. Fill in the reference diagram below to illustrate the above program's memory after line 3 is executed.

   Name Space	Object Space
   a
   b
   c

2. What will lines 4, 5, and 6 print to the command line when they are executed?

3. Fill in the reference diagram below to illustrate the above program's memory after line 7 is executed.

   Name Space	Object Space
   a
   b
   c

4. What will lines 8, 9, and 10 print to the command line when they are executed?